Re: img.src = null（原：src 与 srcset（或是 src-N）的 JS 交互）

img.src = '' 鐨勮涓哄湪鐜板湪娴忚鍣ㄩ噷璨屼技鏄細

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2013/10/26 Kang-Hao (Kenny) Lu <kanghaol@oupeng.com>

> (2013/10/25 21:52), John Hax wrote:
> > 1鐨勬柟娉曟槸鎶奿mg.src鏄庣‘涓烘渶缁堟樉绀虹殑鍥剧墖锛屼篃灏辨槸鎺掗櫎浜嗗悓鏃惰缃畇rcset/src
> > 鐨刢ase銆備篃灏辨槸璇村鏋滄墜鍔ㄨ缃簡src锛屽氨瑕嗙洊浜唖rcset鐨勮缃�傞櫎闈炰綘鍐�
> > img.src = null锛堝綋鍓嶈鑼冩湭瀵硅繖鏍峰簲璇ユ墽琛岀殑琛屼负鍋氬嚭鏄庣‘瑙勫畾锛屾祻瑙堝櫒涓�鑸�
> > 鏄拷鐣ャ�備絾濡傛灉閲囧彇1锛屽垯鍙栨秷瀵箂rcset鐨勮鐩栨槸姣旇緝鍚堢悊鐨勮涓猴紝涓旀琛屼负涓�
> > 娴忚鍣ㄥ綋鍓嶈涓烘槸鍏煎鐨勶級銆�
>
> 褰撳墠瑙勮寖浠湁瀵� "img.src = null" 瀵硅繖鏍峰簲璇ユ墽琛岀殑琛屼负鍋氬嚭鏄庣‘瑙勫畾锛岃鍙傝��
> WebIDL 灞炴�ц鍊肩畻娉昜1]涓� ECMAScript 鍊艰浆鎴� IDL DOMString 鍊肩殑绠楁硶[2]銆傝繖
> 閲岀殑鍏抽敭鏄�
>
> interface HTMLImageElement : HTMLElement {
>            ...
>            attribute DOMString src;
>            ...
> }
>
> 鐨� attribute 鍓嶉潰鏈夋病鏈� [TreatNullAs=EmptyString] 鏍囩銆傛病鏈夊氨鏄� null 浼�
> 琚浆鎴� "null"銆�
>
> 褰撶劧锛屾湁鏄庣‘瑙勫畾璺熷悎涓嶅悎瀹炵幇鎴栨槸鍚堜笉鍚堢悊鏄袱鍥炰簨锛宻rc 灞炴�ц涓嶈鏈�
> [TreatNullAs=EmptyString] 涔熸湁浜夎繃[3]銆傜洰鍓嶆槸
>
>   瑙勮寖 = 鏂� Firefox = IE 鈮� 鏃� Firefox = WebKit
>
> 鐨勬牱瀛愩��
>
> [1] http://www.w3.org/html/ig/zh/wiki/WebIDL#dfn-attribute-setter

> [2]
> http://dev.w3.org/2006/webapi/WebIDL/#dfn-convert-idl-to-ecmascript-value

> [3] https://www.w3.org/Bugs/Public/show_bug.cgi?id=21668

>
> (2013/10/25 23:39), Kang-Hao (Kenny) Lu wrote:
> >    HTML                       <img src=xxx srcset=xxx />
> > +  涓嶆敮鎸� srcset 鐨� JS 搴� 1   璁剧疆浜� .src
> > +  鏀寔 srcset 鐨� JS 搴� 2     璁剧疆浜� .srcset
> >
> > 閭ｈ繖涓椂鍊� JS 搴� 2 浼氫笉璧蜂綔鐢ㄣ�傛敮鎸� .srcset 鐨� JS 搴撶殑瀹屾暣姝ｇ‘鍐欐硶鏄�
> >
> >   img.src = null;鈥�
> >   img.srcset = 鏂板��;
>
> 鎵�浠ヨ繖閲岀殑姝ｇ‘鍐欐硶搴旇鏄�
>
>   img.src = "";
>   img.srcset = 鏂板��;
>
> 銆備笉杩囨垜鎹釜鏂瑰悜闂紝搴旇寰堝浜洪兘鏈夋敞鎰忓埌鍦� DOM 閲� null 澶у浼氬彉鎴�
> "null"锛宨mg.src 鐨勭壒鍒箣澶勫湪鍝紵
>
>
> 璇濊锛屾垜鎰熻澶氫簡瑙� WebIDL 瀵瑰緢澶氫汉鐪嬭鑼冮兘寰堟湁甯姪锛屾瘮濡備箣鍓�
> [ArrayClass] 鐨勮璁篬4]鎴栬鎴戜滑搴旇浼樺厛缈昏瘧 WebIDL锛�
>
> [4]
> http://lists.w3.org/Archives/Public/public-html-ig-zh/2012Jun/thread#msg18

>
> 浠ヤ笂
>
> Kenny
> --
> Web Specialist, Opera Sphinx Team, Oupeng Browser, Beijing
> Try Sphinx: http://sphinx.oupeng.com/

>
>

Received on Sunday, 27 October 2013 13:57:32 UTC