WCAG2.0指南

2008 年 12 月 11 日 W3C 推薦標(biāo)準(zhǔn)

WCAG 2.0 指南

1 可感知的
1.1 為所有非文本內(nèi)容提供文本替代方案，使其可以轉(zhuǎn)化 　　為用戶需要的其他格式，比如，大字排版、盲文、語音、符號或者更簡單的語言。
1.2 為基于時間的媒體提供替代方案。
1.3 在不丟失信息和結(jié)構(gòu)的情況下，創(chuàng)建的內(nèi)容可以在不通的方式中展現(xiàn)。例如：更簡單的布局。
1.4 使用戶更容易看到和聽到內(nèi)容，包括區(qū)分前景色和背景色。

2 可操作的

2.1 讓所有功能都能有效的通過鍵盤操作。
2.2 要提供給用戶足夠的時間去閱讀和使用內(nèi)容。
2.3 不要設(shè)計已知的可以導(dǎo)致癲癇發(fā)作的內(nèi)容。

2.4 提供可以幫助用戶導(dǎo)航、查找內(nèi)容以及確定當(dāng)前所在位置的方法。

3 可理解的

3.1 讓文字內(nèi)容可讀并且可理解。
3.2 讓網(wǎng)頁在可預(yù)見的方式中呈現(xiàn)和交互。
3.3 幫助用戶避免和糾正錯誤。
4 健壯性
4.1 最大程度的兼容當(dāng)前和未來的用戶代理，包括輔助技術(shù)。

WCAG2.0 指南

本節(jié)為規(guī)范內(nèi)容。

1.1.1 Non-text Content: All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below. (Level A)
1.1.1非文本內(nèi)容：所有展示給用戶的非文本內(nèi)容都要有一個提供等價目的的文本替代方案。除了下面列出的情況：（A 級）
Controls, Input: If non-text content is a control or accepts user input, then it has a name that describes its purpose. (Refer to Guideline 4.1 for additional requirements for controls and content that accepts user input.)
控件、輸入：如果非文本內(nèi)容是一個控件或者可接受用戶的輸入，那么它需要有一個名字來描述它的目的。（對可接受用戶輸入的控件和內(nèi)容的額外要求可參看指南 4.1）
Time-Based Media: If non-text content is time-based media, then text alternatives at least provide descriptive identification of the non-text content. (Refer to Guideline 1.2 for additional requirements for media.)
基于時間的媒體：如果非文本內(nèi)容是基于時間的媒體，那么文本替代方案至少要提供描述性信息來標(biāo)識非文本內(nèi)容。
Test: If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives at least provide descriptive identification of the non-text content.
測試：如果非文本內(nèi)容是一個測試或者習(xí)題，以文本形式展示就會失效，那么文本替代方案至少要提供描述性的信息來標(biāo)識非文本內(nèi)容。
Sensory: If non-text content is primarily intended to create a specific sensory experience, then text alternatives at least provide descriptive identification of the non-text content.
感官：如果非文本內(nèi)容主要是為了創(chuàng)建一個具體的感官體驗，那么文本替代方案至少要提供描述性的信息來標(biāo)識非文本內(nèi)容。
CAPTCHA: If the purpose of non-text content is to  that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content are provided, and alternative forms of CAPTCHA using output modes for different types of sensory perception are provided to accommodate different disabilities.
驗證碼：如果非文本的內(nèi)容是用來確定是用戶而不是電腦在訪問內(nèi)容，那么應(yīng)提供用來識別和描述非本文內(nèi)容的文本替代方案并
且提供不同類型感官可感知的輸出方案，作為驗證碼的替代方式來適應(yīng)不同的殘障。
Decoration, Formatting, Invisible: If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it is implemented in a way that it can be ignored by assistive technology.
裝飾、格式、不可見：如果非文本內(nèi)容是純粹的裝飾或者僅僅用于視覺格式又或者對用戶不可見，那么它采用一種使輔助技術(shù)可
以忽略它的實現(xiàn)方式。

1.2.1 Audio-only and Video-only (Prerecorded): For prerecorded audio-only and prerecorded video-only media, the following are true, except when the audio or video is a media alternative for text and is clearly labeled as such: (Level A)
1.2.1純視頻和純音頻（預(yù)先錄制的）：對于預(yù)先錄制好的純音頻和純視頻，要遵循下面要求，除非視頻或音頻是文字的媒體替代方案并且清晰地標(biāo)明。（A 級）
Prerecorded Audio-only: An alternative for time-based media is provided that presents equivalent information for prerecorded audio-only content.
預(yù)先錄制好的純音頻：為預(yù)先錄制好的純音頻內(nèi)容提供一個用于展示等價信息的基于時間的媒體替代方案。
Prerecorded Video-only: Either an alternative for time-based media or an audio track is provided that presents equivalent information for prerecorded video-only content.
預(yù)先錄制好的純視頻：為預(yù)先錄制好的純音頻內(nèi)容提供一個用于展示等價信息的的基于時間的媒體或者音軌的替代方案。
1.2.2Captions (Prerecorded): Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such. (Level A)
1.2.2字幕（預(yù)先錄制好的）：為同步媒體中所有預(yù)先錄制好的音頻提供字幕，除非媒體是文字的媒體替代方案并且清晰地標(biāo)明。（A 級）
1.2.3Audio Description or Media Alternative (Prerecorded): An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such. (Level A)
1.2.3音頻描述或者媒體代替方案（預(yù)先錄制好的）：為同步媒體提供基于時間的媒體替代方案或者預(yù)先錄制的視頻的音頻描述，除非媒體是文字的媒體替代方案并且清晰的表明。（A 級）
1.2.4Captions (Live): Captions are provided for all live audio content in synchronized media. (Level AA)
1.2.4字幕（直播）：為同步媒體中的所有直播的音頻內(nèi)容提供字幕。（AA 級）
1.2.5Audio Description (Prerecorded): Audio description is provided for all prerecorded video content in synchronized media. (Level AA)
1.2.5音頻描述（預(yù)先錄制好的）：為同步媒體中的左右預(yù)先錄制的視頻提供音頻描述。（AA 級）
1.2.6Sign Language (Prerecorded): Sign language interpretation is provided for all prerecorded audio content in synchronized media. (Level AAA)
1.2.6手語（預(yù)先錄制好的）：為同步媒體中的所有預(yù)先錄制好的音頻內(nèi)容提供手語解釋。（AAA 級）
1.2.7Extended Audio Description (Prerecorded): Where pauses in foreground audio are insufficient to allow audio descriptions to convey the sense of the video, extended audio description is provided for all prerecorded video content in synchronized media. (Level AAA)
1.2.7擴(kuò)展的音頻描述（預(yù)先錄制好的）：當(dāng)前景音暫停，音頻描述不足以傳達(dá)視頻的意義時，要為同步媒體中所有預(yù)先錄制好的音頻內(nèi)容提供擴(kuò)展的音頻描述。（AAA 級）
1.2.8Media Alternative (Prerecorded): An alternative for time- based media is provided for all prerecorded synchronized media and for all prerecorded video-only media. (Level AAA)
1.2.8媒體替代方案（預(yù)先錄制好的）：為所有預(yù)先錄制好的同步媒體和預(yù)先錄制好的純視頻媒體提供基于時間的媒體替代方案。（AAA 級）
1.2.9Audio-only (Live): An alternative for time-based media that presents equivalent information for live audio-only content is provided. (Level AAA)
1.2.9 純音頻（直播）：為直播的純音頻內(nèi)容提供用于展示等價信息的基于時間的媒體替代方案。（AAA 級）

1.3.1 Info and Relationships: Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text. (Level A)
1.3.1信息和關(guān)系：表現(xiàn)所傳遞出的信息、結(jié)構(gòu)、關(guān)系可以通過編程方式?jīng)Q定或者以有效的文本形式存在。（A 級）
1.3.2Meaningful Sequence: When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined. (Level A)
1.3.2順序是有意義的：當(dāng)內(nèi)容的順序可以影響它本身的含義，可以利用程序來確定一個正確的閱讀順序（A 級）
1.3.3Sensory Characteristics: Instructions provided for understanding and operating content do not rely solely on sensory characteristics of components such as shape, size, visual location, orientation, or sound. (Level A)
1.3.3 感官特征：為理解和操作內(nèi)容提供的說明不應(yīng)該僅僅依賴于組件的感官特征，比如：形狀、大小、視覺位置、方向或者聲音。（A 級）
Note: For requirements related to color, refer to Guideline 1.4.
注：顏色相關(guān)的要求，參看：指南 1.4

1.4.1Use of Color: Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. (Level A)
顏色的使用：顏色不應(yīng)做為傳遞信息、指示操作、提示響應(yīng)或者區(qū)別
可視元素的唯一方法。（A 級）
Note: This success criterion addresses color perception specifically. Other forms of perception are covered in Guideline 1.3 including programmatic access to color and other visual presentation coding.
提示：這個成功標(biāo)準(zhǔn)專門解決顏色的感知。指南 1.3 涵蓋了其他感知形式，包括以編程的方式獲取顏色和其他視覺表現(xiàn)的代碼。
1.4.2Audio Control: If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume independently from the overall system volume level. (Level A)
1.4.2音頻控制：如果一個網(wǎng)頁上任何自動播放的音頻超過 3 秒，就需要一個暫停或者停止的有效機(jī)制，或者一個獨立于所有系統(tǒng)聲音級別的控制音頻聲音有效機(jī)制。（A 級）
Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.
提示：由于任何未能滿足此成功標(biāo)準(zhǔn)的內(nèi)容都會干擾用戶使用整個網(wǎng)頁，所以網(wǎng)頁上的所有內(nèi)容（無論它是否滿足其他的成功標(biāo)準(zhǔn)）都必須實現(xiàn)這個成功標(biāo)準(zhǔn)。參看：一致性要求 5：互不干涉。
1.4.3Contrast (Minimum): The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following: (Level AA)
1.4.3對比度（最小值）：除了下面幾點，文本和圖片式文本的視覺感知的對比度比至少為 4.5:1：（AA 級）
Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;大號文本：可放大的文本和圖片式的可放大文本的對比度比至少為 3:1；
Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
附屬的：文本或者圖片式的文本是未激活的用戶組件的一部分、純裝飾性、對任何人不可見，或者一個包含有意義的視覺內(nèi)容的
圖片的一部分，沒有對比度要求。
Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.
Logo 類型：文字是 logo 或者是品牌名字的一部分可以沒有最小對比度的要求。
1.4.4Resize text: Except for captions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality. (Level AA)
1.4.4調(diào)整文本：除了字幕和圖片式文本，在不使用輔助技術(shù)的情況下文本可以放大到 200%并且沒有內(nèi)容和功能的損失。
1.4.5Images of Text: If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following: (Level AA)
1.4.5圖片式文字：如果視覺感知方式能用技術(shù)能實現(xiàn)，除了下列情況， 使用文本傳遞信息要比圖片式文字好：（AA 級）
Customizable: The image of text can be visually customized to the user's requirements;
可定制的：可以根據(jù)用戶需要的視覺定制的圖片式文本。
Essential: A particular presentation of text is essential to the information being conveyed.
必不可少的：文字是一個必不可少的傳遞信息的具體感知方式。
Note: Logotypes (text that is part of a logo or brand name) are considered essential.
提示：logo 類（logo 或者品牌名稱的一部分）必須要考慮。
1.4.6Contrast (Enhanced): The visual presentation of text and images of text has a contrast ratio of at least 7:1, except for the following: (Level AAA)
1.4.6對比度（增強(qiáng)的）：除了下列情況，文本和圖片式文本的視覺感知的對比度比最少為 7：1：（AAA 級）
Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 4.5:1;
大號文本：可放大的文本和圖片式的可放大文本的對比度比至少為 4.5:1；
Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
附屬的：文本或者圖片式的文本是未激活的用戶組件的一部分、純裝飾性、對任何人不可見，或者一個包含有意義的視覺內(nèi)容的圖片的一部分，沒有對比度要求。
Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.
Logo 類型：文字是 logo 或者是品牌名字的一部分可以沒有最小對比度的要求。
1.4.7Low or No Background Audio: For prerecorded audio-only content that (1) contains primarily speech in the foreground, (2) is not an audio CAPTCHA or audio logo, and (3) is not vocalization intended to be primarily musical expression such as singing or rapping, at least one of the following is true: (Level AAA)
1.4.7輕聲或者無背景音：對于這幾種預(yù)先錄制好的只有音頻的內(nèi)容，
1）包含主要話語的前景音，2）不是一個音頻驗證碼或者音頻 logo，3）沒有發(fā)聲，打算主要音樂用來表達(dá)，比如唱歌和說唱，那么要至少要符合下列其中一點：（AAA 級）
No Background: The audio does not contain background sounds.
沒有背景音：音頻不要包含背景音。
Turn Off: The background sounds can be turned off.
關(guān)閉：背景音可以被關(guān)閉。
20 dB: The background sounds are at least 20 decibels lower than the foreground speech content, with the exception of occasional sounds that last for only one or two seconds.
20 分貝：背景音至少要比前景話語內(nèi)容低于 20 分貝，除了偶爾僅僅持續(xù) 1~2 秒的聲音。
Note: Per the definition of "decibel," background sound that meets this requirement will be approximately four times quieter than the foreground speech content.
注：根據(jù)“分貝”的定義，背景音達(dá)到這個要求需要比前景話語內(nèi)容大約安靜 4 倍。
1.4.8Visual Presentation: For the visual presentation of blocks of text, a mechanism is available to achieve the following: (Level AAA)
1.4.8視覺感知：對于塊狀的文本，需要提供一種有效的機(jī)制來實現(xiàn)下面的要求：（AAA 級要求）
1.Foreground and background colors can be selected by the user.
用戶可以選擇前景色和后景色。
2.Width is no more than 80 characters or glyphs (40 if CJK).
寬度不能大于 80 個字符或符號（中、日、韓 40 個字）
3.Text is not justified (aligned to both the left and the right margins).
文本不需要兩端對齊（同時將左右兩端對齊）
4.Line spacing (leading) is at least space-and-a-half within paragraphs, and paragraph spacing is at least 1.5 times larger than the line spacing.
段落中的行間距至少是 1.5 倍行高，段落間距至少是行間距的1.5 倍。
5.Text can be resized without assistive technology up to 200 percent in a way that does not require the user to scroll horizontally to read a line of text on a full-screen window.
不使用輔助技術(shù)，文本可以調(diào)整大小到 200%并且在全屏下不需要用戶水平滾動去閱讀一行文本。
1.4.9Images of Text (No Exception): Images of text are only used for pure decoration or where a particular presentation of text is essential to the information being conveyed. (Level AAA)
1.4.9 圖片式文本（沒有例外）：圖片式文本只用于純裝飾或者文字是一個必不可少的傳遞信息的具體感知方式。（AAA 級）
Note: Logotypes (text that is part of a logo or brand name) are considered essential.
注：logo 類（logo 或者品牌名稱的一部分）必須要考慮。

2.1.1 Keyboard: All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints. (Level A)
2.1.1鍵盤：內(nèi)容的所有功能都可以使用鍵盤接口操作，不對單個按鍵有具體的時間要求，除非底層功能需要依賴用戶的移動路徑而不只是路徑的終點來輸入。（A 級）
Note 1: This exception relates to the underlying function, not the input technique. For example, if using handwriting to enter text, the input technique (handwriting) requires path-dependent input but the underlying function (text input) does not.
注 1：上面描述的例外只適用于與底層功能相關(guān)的范疇，而不針對輸入技術(shù)。舉個例子：如果使用手寫去輸入文字，手寫需要依賴路徑輸入，但是底層的功能（文字輸入功能）并不需要依賴路徑。
Note 2: This does not forbid and should not discourage providing mouse input or other input methods in addition to keyboard operation.
注 2：這并不是禁止或者阻止提供鼠標(biāo)或者其他除鍵盤以外的輸入方法。
2.1.2No Keyboard Trap: If keyboard focus can be moved to a component of the page using a keyboard interface, then focus can be moved away from that component using only a keyboard interface, and, if it requires more than unmodified arrow or tab keys or other standard exit methods, the user is advised of the method for moving focus away. (Level A)
2.1.2禁止鍵盤陷阱：如果焦點通過鍵盤接口聚焦到到頁面上的一個組件上，那么焦點只能使用鍵盤接口才可以離開這個組件，如果需要除原生箭頭鍵或者 Tab 鍵以外的其他標(biāo)準(zhǔn)的退出方法，需要將移出焦點的方法傳達(dá)給用戶。（A 級）
Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.
注：由于任何未能滿足此成功標(biāo)準(zhǔn)的內(nèi)容都會干擾用戶使用整個網(wǎng)頁，
所以網(wǎng)頁上的所有內(nèi)容（無論它是否滿足其他的成功標(biāo)準(zhǔn)）都必須實現(xiàn)這個成功標(biāo)準(zhǔn)。參看：一致性要求 5：互不干涉。
2.1.3Keyboard (No Exception): All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes. (Level AAA)
2.1.3 鍵盤（沒有例外）：內(nèi)容的所有功能都可以使用鍵盤接口操作，不對單個按鍵有具體的時間要求。（AAA 級）

2.2.1 Timing Adjustable: For each time limit that is set by the content, at least one of the following is true: (Level A)
2.2.1可調(diào)整時間：每一個為內(nèi)容設(shè)置的時間限制，至少符合下面其中一點：（A 級）
Turn off: The user is allowed to turn off the time limit before encountering it; or
關(guān)閉：在遇到時間限制之前可以允許用戶關(guān)閉它；或者
Adjust: The user is allowed to adjust the time limit before encountering it over a wide range that is at least ten times the length of the default setting; or
調(diào)整：在遇到時間限制之前可以允許用戶調(diào)整它到一個至少是默認(rèn)設(shè)置 10 倍長度的范圍；或者
Extend: The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, "press the space bar"), and the user is allowed to extend the time limit at least ten times; or延長：在超時之前要警告用戶，并且給出至少 20 秒的時間，讓用戶可以使用一個簡單的操作（例如“按空格鍵”）來延長時間限
制，同時允許用戶延長至少 10 倍的時間；或者
Real-time Exception: The time limit is a required part of a real-time event (for example, an auction), and no alternative to the time limit is possible; or
實時例外：時間限制是實時事件的一個必要部分（例如“一個拍賣”），并且可能沒有方案替代時間限制；或者
Essential Exception: The time limit is essential and extending it would invalidate the activity; or
必不可少例外：時間限制是必不可少的并且延長它可能會使活動無效；或者
20 Hour Exception: The time limit is longer than 20 hours.
20 小時例外：時間限制大于 20 小時。
Note: This success criterion helps ensure that users can complete tasks without unexpected changes in content or context that are a result of a time limit. This success criterion should be considered in conjunction with Success Criterion 3.2.1, which puts limits on changes of content or context as a result of user action.
注：這個成功標(biāo)注會幫助保證用戶可以完成任務(wù)不會由于時間限制出
現(xiàn)突然的更改內(nèi)容或者上下文的結(jié)果。這個成功標(biāo)準(zhǔn)應(yīng)該連同成功標(biāo)準(zhǔn) 3.2.1 仔細(xì)考慮，讓修改內(nèi)容或上下文的限制作為用戶操作的結(jié)果。
2.2.2Pause, Stop, Hide: For moving,blinking, scrolling, or auto- updating information, all of the following are true: (Level A)
2.2.2暫停，停止，隱藏：對于移動，閃爍，滾動或者其他自動更新的信息，應(yīng)該符合一下全部要求：（A 級）
Moving, blinking, scrolling: For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and
移動、閃爍、滾動：對于任何符合以下特征的移動，閃爍，滾動的信息，（1）自動開始，（2）持續(xù)時間大于 5 秒并且（3）與其他內(nèi)容同時展示，需要提供個用戶一個機(jī)制用來暫停、停止或隱藏它，除非移動，閃爍，滾動是一個活動必不可少的一部分。
Auto-updating: For any auto-updating information that (1) starts automatically and (2) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto- updating is part of an activity where it is essential.
自動更新：對于任何符合以下特征的自動更新的信息，（1）自動開始并且（2）與其他內(nèi)容同時展示，需要提供給用戶一個機(jī)
制用來暫停、停止或隱藏它或者控制更新頻率，除非自動更新是活動必不可少的一部分。
Note 1: For requirements related to flickering or flashing content, refer to Guideline 2.3.
注 1：關(guān)于閃爍和閃光的相關(guān)要求可參看指南 2.3。
Note 2: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.
注 2：由于任何未能滿足此成功標(biāo)準(zhǔn)的內(nèi)容都會干擾用戶使用整個網(wǎng)頁，所以網(wǎng)頁上的所有內(nèi)容（無論它是否滿足其他的成功標(biāo)準(zhǔn)）都必須實現(xiàn)這個成功標(biāo)準(zhǔn)。參看：一致性要求 5：互不干涉。
Note 3: Content that is updated periodically by software or that is streamed to the user agent is not required to preserve or present information that is generated or received between the initiation of the pause and resuming presentation, as this may not be technically possible, and in many situations could be misleading to do so.
注 3：由軟件定期更新的或者傳給用戶代理不需要請求保存內(nèi)容，或者在暫停和重新恢復(fù)中生成或接收展示的信息，類似這些可能沒有技術(shù)方案并且在很多情況下可能是誤導(dǎo)性的。
Note 4: An animation that occurs as part of a preload phase or similar situation can be considered essential if interaction cannot occur during that phase for all users and if not indicating progress could confuse users or cause them to think that content was frozen or broken.
注 4：以作為預(yù)加載階段的一部分或者類似情形的形式出現(xiàn)的動畫必須要考慮如果在這個階段不與用戶發(fā)生交互并且沒有顯示進(jìn)度可能導(dǎo)致用戶困惑或者認(rèn)為內(nèi)容凍結(jié)或者損壞。
2.2.3No Timing: Timing is not anessential part of the event or activity presented by the content, except for non-interactive synchronized media and real-time events. (Level AAA)
2.2.3不定時：除非是非交互的同步媒體和實時事件，否則定時不應(yīng)該是展示事件或者活動內(nèi)容的必不可少的部分。（AAA 級）
2.2.4Interruptions: Interruptions can be postponed or suppressed by the user, except interruptions involving an emergency. (Level AAA)
2.2.4中斷：除非中斷涉及到一個緊急情況，否則用戶可以推遲或者禁止中斷。（AAA 級）
2.2.5Re-authenticating: When an authenticated session expires, the user can continue the activity without loss of data after re- authenticating. (Level AAA)
2.2.5 重新驗證：當(dāng)一個驗證會話失效，在重新驗證之后不 應(yīng)丟失數(shù)據(jù)， 用戶可以繼續(xù)進(jìn)行活動。（AAA 級）

2.3.1 Three Flashes or Below Threshold: Web pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds. (Level A)
2.3.1三次閃爍或者低于閾值：網(wǎng)頁中不要包含任何每秒大于三次或者低于普通和紅色閃爍閾值的閃爍。（A 級）
Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.
注：由于任何未能滿足此成功標(biāo)準(zhǔn)的內(nèi)容都會干擾用戶使用整個網(wǎng)頁，所以網(wǎng)頁上的所有內(nèi)容（無論它是否滿足其他的成功標(biāo)準(zhǔn)）都必須實現(xiàn)這個成功標(biāo)準(zhǔn)。參看：一致性要求 5：互不干涉。
2.3.2Three Flashes: Web pages do not contain anything that flashes more than three times in any one second period. (Level AAA)
2.3.2 三次閃爍：網(wǎng)頁中不要包含任何每秒大于三次的閃爍（AAA 級）

2.4.1 Bypass Blocks: A mechanism is available to bypass blocks of content that are repeated on multiple Web pages. (Level A)
2.4.1跳過區(qū)域：需要一種機(jī)制可以讓用戶跳過在多個網(wǎng)頁上重復(fù)的內(nèi)容區(qū)域。
2.4.2Page Titled: Web pages have titles that describe topic or purpose. (Level A)
2.4.2頁面標(biāo)題：網(wǎng)頁要有一個描述主題或者用途的標(biāo)題。（A 級）
2.4.3Focus Order: If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components receive focus in an order that preserves meaning and operability. (Level A)
2.4.3焦點序列：如果網(wǎng)頁可以按順序?qū)Ш讲⑶覍?dǎo)航順序影響含義或者
操作，可聚焦的組件應(yīng)在一個可以保護(hù)含義和可操作性的序列中接收焦點。（A 級）
2.4.4Link Purpose (In Context): The purpose of each link can be determined from the link text alone or from the link text together with its programmatically determined link context, except where the purpose of the link would be ambiguous to users in general. (Level A)
2.4.4鏈接用途（在上下文中）：僅從鏈接的文本或者將鏈接文本和它編程確定的鏈接上下文關(guān)聯(lián)在一起與就能確定鏈接的目的，一般來說除非鏈接的目的是用來迷惑用戶。（A 級）
2.4.5Multiple Ways: More than one way is available to locate a Web page within a set of Web pages except where the Web Page is the result of, or a step in, a process. (Level AA)
2.4.5多種方式：在一組網(wǎng)頁中有多種方式去有效的定位一個網(wǎng)頁，除非網(wǎng)頁是一個步驟的結(jié)果，或者一個步驟，一個進(jìn)程。（AA 級）
2.4.6Headings and Labels: Headings and labels describe topic or purpose. (Level AA)
2.4.標(biāo)題和標(biāo)簽：標(biāo)題和標(biāo)簽應(yīng)描述主體或者用途。（AA 級）
2.4.7Focus Visible: Any keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible. (Level AA)
2.4.7可視的焦點：任何鍵盤操作的用戶界面需要一個鍵盤焦點的指示是可視的操作模式。（AA 級）
2.4.8Location: Information about the user's location within a set of Web pages is available. (Level AAA)
2.4.8定位：一組網(wǎng)頁中關(guān)于用戶定位的信息應(yīng)該是有效的。（AAA 級）
2.4.9Link Purpose (Link Only): A mechanism is available to allow the purpose of each link to be identified from link text alone, except where the purpose of the link would be ambiguous to users in general. (Level AAA)
2.4.8 鏈接用途（僅鏈接本身）：需要提供一個有效的機(jī)制允許僅僅從鏈接的文本就確定每一個鏈接的用途，一般來說除非鏈接的目的就是用來迷惑用戶的。（AAA 級）
2.4.10 Section Headings: Section headings are used to organize the content. (Level AAA)
2.4.10 章節(jié)標(biāo)題：使用章節(jié)標(biāo)題來組織內(nèi)容。（AAA 級）
Note 1: "Heading" is used in its general sense and includes titles and other ways to add a heading to different types of content.
注 1：” heading 標(biāo)簽”用來標(biāo)識內(nèi)容的一般語義，包括標(biāo)題和其他為不
同類型內(nèi)容添加一個標(biāo)題的方法。
Note 2: This success criterion covers sections within writing, not user interface components. User Interface components are covered under Success Criterion 4.1.2.
注 2：這個成功標(biāo)準(zhǔn)包含章節(jié)中寫作的部分，不涵蓋用戶界面組件。成功標(biāo)準(zhǔn) 4.1.2 涵蓋了用戶界面組件的信息。

3.1.1 Language of Page: The default human language of each Web page can be programmatically determined. (Level A)
3.1.1頁面語言：每個網(wǎng)頁默認(rèn)的人類語言可以由程序來確定。（A 級）
3.1.2Language of Parts: The human language of each passage or phrase in the content can be programmatically determined except for proper names, technical terms, words of indeterminate language, andwords or phrases that have become part of the vernacular of the immediately surrounding text. (Level AA)
3.1.2網(wǎng)頁中各個部分的語言：內(nèi)容里的每一段或者每一個短語的人類語言都可以由程序來確定。除了專有名稱、技術(shù)術(shù)語、無法確定語言的詞語以及部分緊鄰文本周圍的方言。（AA 級）
3.1.3Unusual Words: A mechanism is available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon. (Level AAA)
3.1.3非常用詞匯：需要有一種有效的機(jī)制，來識別非常用或限制級的詞語或詞組的具體含義，包括成語和難懂的術(shù)語。（AAA 級）
3.1.4Abbreviations: A mechanism for identifying the expanded form or meaning of abbreviations is available. (Level AAA)
3.1.4縮寫：需要有一種有效機(jī)制，來識別縮寫的全稱或含義。（AAA 級）
3.1.5Reading Level: When text requires reading ability more advanced than the lower secondary education level after removal of proper names and titles, supplemental content, or a version that does not require reading ability more advanced than the lower secondary education level, is available. (Level AAA)
3.1.5閱讀級別： 當(dāng)刪除專有名稱、標(biāo)題和補(bǔ)充內(nèi)容之后的文本還需要高于初中教育水平閱讀能力的時候，就要有一個不需要閱讀能力高于初中教育水平的版本。（AAA 級）
3.1.6Pronunciation: A mechanism is available for identifying specific pronunciation of words where meaning of the words, in context, is ambiguous without knowing the pronunciation. (Level AAA)
3.1.6 發(fā)音：當(dāng)詞語在上下文中不知道其發(fā)音就會引起歧義時，需要一個機(jī)制來識別詞語的具體發(fā)音。（AAA 級）

3.2.1 On Focus: When any component receives focus, it does not initiate a change of context. (Level A)
3.2.1聚焦：任何組件當(dāng)它接收焦點的時候，不能導(dǎo)致上下文的變化。（A 級）
3.2.2On Input: Changing the setting of any user interface component does not automatically cause a change of context unless the user has been advised of the behavior before using the component. (Level A)
3.2.2輸入：除非用戶在使用組件之前被告知，否則任何改變用戶界面的設(shè)置都不應(yīng)該自動導(dǎo)致上下文的變化。（A 級）
3.2.3Consistent Navigation: Navigational mechanisms that are repeated on multiple Web pages within a set of Web pages occur in the same relative order each time they are repeated, unless a change is initiated by the user. (Level AA)
3.2.3一致的導(dǎo)航：除非用戶改變導(dǎo)航機(jī)制，否則在一組網(wǎng)頁中，多個網(wǎng)頁重復(fù)出現(xiàn)的時候，他們的相對位置都應(yīng)該是相同的。（AA 級）
3.2.4Consistent Identification: Components that have the same functionality within a set of Web pages are identified consistently. (Level AA)
3.2.4一致的識別性：在一組網(wǎng)頁中相同功能的組件的識別性要一致。（AA 級）
3.2.5Change on Request: Changes of context are initiated only by user request or a mechanism is available to turn off such changes. (Level AAA)
3.2.5 應(yīng)要求改變：只有用戶的要求才能導(dǎo)致上下文的改變，或者提供一種關(guān)閉上下文改變的有效機(jī)制。（AAA 級）

3.3.1 Error Identification: If an input error is automatically detected, the item that is in error is identified and the error is described to the user in text. (Level A)
3.3.1錯誤識別：如果一個輸入錯誤是可以自動檢測的，那么這個項目的錯誤應(yīng)被用戶發(fā)現(xiàn)，并且用文字進(jìn)行表述。（A 級）
3.3.2Labels or Instructions: Labels or instructions are provided when content requires user input. (Level A)
3.3.2標(biāo)簽或操作說明：當(dāng)內(nèi)容需要用戶輸入的時候，需要提供標(biāo)簽或者操作說明。（A 級）
3.3.3Error Suggestion: If an input error is automatically detected and suggestions for correction are known, then the suggestions are provided to the user, unless it would jeopardize the security or purpose of the content. (Level AA)
3.3.3錯誤提示：如果可以自動檢測輸入錯誤并且提供已知的修改建議， 那么除非提示會危害到內(nèi)容的安全和目的，否則應(yīng)該將它提供給用戶。（AA 級）
3.3.4Error Prevention (Legal, Financial, Data): For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, at least one of the following is true: (Level AA)
3.3.4錯誤預(yù)防（法律、金融、數(shù)據(jù)）：對于用戶操作可以引起法律承諾或者金融交易的網(wǎng)頁，修改或者刪除數(shù)據(jù)存儲系統(tǒng)里用戶可操作的數(shù)據(jù)，或者提交用戶驗證的響應(yīng)，至少要遵循以下其中一點：（AA 級）
1.Reversible: Submissions are reversible.
可逆的：提交是可逆的。
2.Checked: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
檢查：檢查用戶輸入的數(shù)據(jù)是否有輸入錯誤并且給用戶提供一個修改他們的機(jī)會。
3.Confirmed: A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.
確認(rèn)：在最后提交之前，需要提供一個檢查、確認(rèn)和修改信息的有效機(jī)制。
3.3.5Help: Context-sensitive help is available. (Level AAA)
3.3.5幫助：提供上下文相關(guān)幫助。（AAA 級別）
3.3.6Error Prevention (All): For Web pages that require the user to submit information, at least one of the following is true: (Level AAA)
3.3.6錯誤預(yù)防（所有）：對于需要用戶提交的信息的網(wǎng)頁，至少要遵循以下其中一點：（AAA 級）
1.Reversible: Submissions are reversible.
可逆的：提交是可逆的。
2.Checked: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
檢查：檢查用戶輸入的數(shù)據(jù)是否有輸入錯誤并且給用戶提供一個修改他們的機(jī)會。
3.Confirmed: A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.
確認(rèn)：在最后提交之前，需要提供一個檢查、確認(rèn)和修改信息的有效機(jī)制。

4.1.1 Parsing: In content implemented using markup languages, elements have complete start and end tags, elements are nested according to their specifications, elements do not contain duplicate attributes, and any IDs are unique, except where the specifications allow these features. (Level A)
4.1.1語法解析：使用標(biāo)記語言來組織內(nèi)容，元素要有完整的開始和結(jié)束標(biāo)簽，要根據(jù)他們的規(guī)范來嵌套，不能包含重復(fù)的屬性，除非規(guī)范允許，否則任何 ID 都是唯一的。（A 級）
Note: Start and end tags that are missing a critical character in their formation, such as a closing angle bracket or a mismatched attribute value quotation mark are not complete.
注：在開始和結(jié)束的標(biāo)簽組成中缺少關(guān)鍵字符，比如：一個右尖括號、屬性值不匹配或者雙引號不完整。
4.1.2Name, Role, Value: For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies. (Level A)
4.1.2 名稱、角色、值：對于所有的用戶界面組件（包括但不限于：表單元素、鏈接以及由腳本生成的組件），他們的名稱和角色可以通過編程確定；狀態(tài)、屬性和值可以通過編程來設(shè)置；這些項目變化的通知對包括輔助技術(shù)在內(nèi)的用戶代理應(yīng)該是可用的。（A 級別）
Note: This success criterion is primarily for Web authors who develop or  their own user interface components. For example, standard HTML controls already meet this success criterion when used according to specification.
注：這個成功標(biāo)準(zhǔn)主要是用于自己開發(fā)或者編寫用戶界面組件腳本的
作者。舉個例子：當(dāng)根據(jù)標(biāo)準(zhǔn)使用 HTML 控件的時候就已經(jīng)達(dá)到了成功的標(biāo)準(zhǔn)。

下載：網(wǎng)站內(nèi)容無障礙指南 2.0 Web Content Accessibility Guidelines _WCAG_ 2.0 中文版.pdf