Is there any difference between
and
</script> <ins class="adsbygoogle" style="display:block" data-ad-client="ca-pub-5408099190056760" data-ad-slot="7305827575" data-ad-format="auto" data-full-width-responsive="true"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> <div class="relativetags"> 相关标签: </div> </div> <div class="fly-panel detail-box" id="flyReply"> <fieldset class="layui-elem-field layui-field-title" style="text-align: center;"> <legend>6条回答</legend> </fieldset> <ul class="jieda" id="jieda"> <li data-id="111"> <a name="item-1111111111"></a> <div class="detail-about detail-about-reply"> <a class="fly-avatar" href="https://www.e-learn.cn/qa/u-125.html"> <img src="https://www.e-learn.cn/qa/data/avatar/000/00/01/small_000000125.jpg" alt=" "> </a> <div class="fly-detail-user"> <a href="https://www.e-learn.cn/qa/u-125.html" class="fly-link"> <cite>攒了一身酷 </cite> </a> </div> <div class="detail-hits"> <span>2020-11-27 08:11</span> </div> </div> <div class="detail-body jieda-body photos"> <blockquote> <h1>Unquoted attribute value syntax</h1> <p>The attribute name, followed by zero or more space characters, followed by a single U+003D EQUALS SIGN character, followed by zero or more space characters, followed by the attribute value, which, in addition to the requirements given above for attribute values, must not contain any literal space characters, any U+0022 QUOTATION MARK characters ("), U+0027 APOSTROPHE characters ('), U+003D EQUALS SIGN characters (=), U+003C LESS-THAN SIGN characters (<), U+003E GREATER-THAN SIGN characters (>), or U+0060 GRAVE ACCENT characters (`), and must not be the empty string.</p> <p>— W3 HTML5 Specification - sec 8.1.2.3. Attributes</p> </blockquote> <div class="appendcontent"> </div> </div> <div class="jieda-reply"> <span class="jieda-zan button_agree" type="zan" data-id='427087'> <i class="iconfont icon-zan"></i> <em>0</em> </span> <span type="reply" class="showpinglun" data-id="427087"> <i class="iconfont icon-svgmoban53"></i> 讨论(0) </span> <div class="jieda-admin"> </div> </div> <div class="comments-mod " style="display: none; float:none;padding-top:10px;" id="comment_427087"> <div class="areabox clearfix"> <form class="layui-form" action=""> <div class="layui-form-item"> <label class="layui-form-label" style="padding-left:0px;width:60px;">发布评论:</label> <div class="layui-input-block" style="margin-left:90px;"> <input type="text" placeholder="不少于5个字" AUTOCOMPLETE="off" class="comment-input layui-input" name="content" /> <input type='hidden' value='0' name='replyauthor' /> </div> <div class="mar-t10"><span class="fr layui-btn layui-btn-sm addhuidapinglun" data-id="427087">提交评论 </span></div> </div> </form> </div> <hr> <ul class="my-comments-list nav"> <li class="loading"> <img src='https://www.e-learn.cn/qa/static/css/default/loading.gif' align='absmiddle' /> 加载中... </li> </ul> </div> </li> <li data-id="111"> <a name="item-1111111111"></a> <div class="detail-about detail-about-reply"> <a class="fly-avatar" href="https://www.e-learn.cn/qa/u-130.html"> <img src="https://www.e-learn.cn/qa/data/avatar/000/00/01/small_000000130.jpg" alt=" "> </a> <div class="fly-detail-user"> <a href="https://www.e-learn.cn/qa/u-130.html" class="fly-link"> <cite>再見小時候 </cite> </a> </div> <div class="detail-hits"> <span>2020-11-27 08:13</span> </div> </div> <div class="detail-body jieda-body photos"> <p>According to the <strong>W3C</strong> there are four types of attribute syntax:</p> <ol> <li>empty attribute syntax</li> <li>unquoted attribute-value syntax</li> <li>single-quoted attribute-value syntax</li> <li>double-quoted attribute-value syntax</li> </ol> <p>These really apply to HTML5, however when referring to < HTML5 the <strong>W3C</strong> says that quotes (single or double) are required based on the doctype (e.g. strict, transitional, etc.) used.</p> <div class="appendcontent"> </div> </div> <div class="jieda-reply"> <span class="jieda-zan button_agree" type="zan" data-id='427084'> <i class="iconfont icon-zan"></i> <em>0</em> </span> <span type="reply" class="showpinglun" data-id="427084"> <i class="iconfont icon-svgmoban53"></i> 讨论(0) </span> <div class="jieda-admin"> </div> </div> <div class="comments-mod " style="display: none; float:none;padding-top:10px;" id="comment_427084"> <div class="areabox clearfix"> <form class="layui-form" action=""> <div class="layui-form-item"> <label class="layui-form-label" style="padding-left:0px;width:60px;">发布评论:</label> <div class="layui-input-block" style="margin-left:90px;"> <input type="text" placeholder="不少于5个字" AUTOCOMPLETE="off" class="comment-input layui-input" name="content" /> <input type='hidden' value='0' name='replyauthor' /> </div> <div class="mar-t10"><span class="fr layui-btn layui-btn-sm addhuidapinglun" data-id="427084">提交评论 </span></div> </div> </form> </div> <hr> <ul class="my-comments-list nav"> <li class="loading"> <img src='https://www.e-learn.cn/qa/static/css/default/loading.gif' align='absmiddle' /> 加载中... </li> </ul> </div> </li> <li data-id="111"> <a name="item-1111111111"></a> <div class="detail-about detail-about-reply"> <a class="fly-avatar" href="https://www.e-learn.cn/qa/u-83.html"> <img src="https://www.e-learn.cn/qa/data/avatar/000/00/00/small_000000083.jpg" alt=" "> </a> <div class="fly-detail-user"> <a href="https://www.e-learn.cn/qa/u-83.html" class="fly-link"> <cite>时光取名叫无心 </cite> </a> </div> <div class="detail-hits"> <span>2020-11-27 08:34</span> </div> </div> <div class="detail-body jieda-body photos"> <p>It is all about the true validity of HTML markup. It's for what W3C (WWW Consortium) work for. Many things might work in HTML but they have to be validated in order to be more carefully recognized by the web browser. You can even omit the <code><html></code> and <code></html></code> tags at the start and end, but it is not recommended at all, nobody does it and it is considered as a 'bad code'.</p> <p>Therefore, it is more valid to put them in quotes.</p> <div class="appendcontent"> </div> </div> <div class="jieda-reply"> <span class="jieda-zan button_agree" type="zan" data-id='427082'> <i class="iconfont icon-zan"></i> <em>0</em> </span> <span type="reply" class="showpinglun" data-id="427082"> <i class="iconfont icon-svgmoban53"></i> 讨论(0) </span> <div class="jieda-admin"> </div> </div> <div class="comments-mod " style="display: none; float:none;padding-top:10px;" id="comment_427082"> <div class="areabox clearfix"> <form class="layui-form" action=""> <div class="layui-form-item"> <label class="layui-form-label" style="padding-left:0px;width:60px;">发布评论:</label> <div class="layui-input-block" style="margin-left:90px;"> <input type="text" placeholder="不少于5个字" AUTOCOMPLETE="off" class="comment-input layui-input" name="content" /> <input type='hidden' value='0' name='replyauthor' /> </div> <div class="mar-t10"><span class="fr layui-btn layui-btn-sm addhuidapinglun" data-id="427082">提交评论 </span></div> </div> </form> </div> <hr> <ul class="my-comments-list nav"> <li class="loading"> <img src='https://www.e-learn.cn/qa/static/css/default/loading.gif' align='absmiddle' /> 加载中... </li> </ul> </div> </li> <li data-id="111"> <a name="item-1111111111"></a> <div class="detail-about detail-about-reply"> <a class="fly-avatar" href="https://www.e-learn.cn/qa/u-22.html"> <img src="https://www.e-learn.cn/qa/data/avatar/000/00/00/small_000000022.jpg" alt=" "> </a> <div class="fly-detail-user"> <a href="https://www.e-learn.cn/qa/u-22.html" class="fly-link"> <cite>误落风尘 </cite> </a> </div> <div class="detail-hits"> <span>2020-11-27 08:34</span> </div> </div> <div class="detail-body jieda-body photos"> <p>Nope both are the same..</p> <p>In HTML 5 Quotes around attributes are just <strong>optional.</strong> (Unless the value has spaces or special characters )</p> <p>But I feel it's a better practice to enclose them in Quotes..</p> <div class="appendcontent"> </div> </div> <div class="jieda-reply"> <span class="jieda-zan button_agree" type="zan" data-id='427085'> <i class="iconfont icon-zan"></i> <em>0</em> </span> <span type="reply" class="showpinglun" data-id="427085"> <i class="iconfont icon-svgmoban53"></i> 讨论(0) </span> <div class="jieda-admin"> </div> </div> <div class="comments-mod " style="display: none; float:none;padding-top:10px;" id="comment_427085"> <div class="areabox clearfix"> <form class="layui-form" action=""> <div class="layui-form-item"> <label class="layui-form-label" style="padding-left:0px;width:60px;">发布评论:</label> <div class="layui-input-block" style="margin-left:90px;"> <input type="text" placeholder="不少于5个字" AUTOCOMPLETE="off" class="comment-input layui-input" name="content" /> <input type='hidden' value='0' name='replyauthor' /> </div> <div class="mar-t10"><span class="fr layui-btn layui-btn-sm addhuidapinglun" data-id="427085">提交评论 </span></div> </div> </form> </div> <hr> <ul class="my-comments-list nav"> <li class="loading"> <img src='https://www.e-learn.cn/qa/static/css/default/loading.gif' align='absmiddle' /> 加载中... </li> </ul> </div> </li> <li data-id="111"> <a name="item-1111111111"></a> <div class="detail-about detail-about-reply"> <a class="fly-avatar" href="https://www.e-learn.cn/qa/u-63.html"> <img src="https://www.e-learn.cn/qa/data/avatar/000/00/00/small_000000063.jpg" alt=" "> </a> <div class="fly-detail-user"> <a href="https://www.e-learn.cn/qa/u-63.html" class="fly-link"> <cite>囚心锁ツ </cite> </a> </div> <div class="detail-hits"> <span>2020-11-27 08:36</span> </div> </div> <div class="detail-body jieda-body photos"> <p>There is no practical difference except</p> <ol> <li>if you validate your page, quotation marks may or may not be needed to avoid error messages, depending on doctype being used</li> <li>if you serve the page with an XML content type to browsers (which is rare and seldom useful), then the quotes are required – otherwise the page is not displayed at all, just an error message</li> <li>if the page is otherwise processed with XML tools, the quotes are necessary.</li> </ol> <p>Otherwise, the quotation marks are really needed only if the attribute value contains a space, a line break, an Ascii quotation mark ("), an Ascii apostrophe ('), a grave accent (`), an equals sign (=), a less than sign (<), or a greater than sign (>). So <code>style = width:20em</code> would work (though it might be seen as somewhat obscure), whereas <code>style = width: 20em</code> would not – due to the space, you would need to write <code>style = "width: 20em"</code>.</p> <p>Many people always write quotation marks around all attribute values, for simplicity. Others think that quotation marks make the code a bit messy, so they omit them when possible.</p> <p>Quite independently of this, <code>src="www.example.com"</code> means a relative URL reference, not what people expect to mean. You probably meant <code>src="http://www.example.com"</code>.</p> <div class="appendcontent"> </div> </div> <div class="jieda-reply"> <span class="jieda-zan button_agree" type="zan" data-id='427083'> <i class="iconfont icon-zan"></i> <em>0</em> </span> <span type="reply" class="showpinglun" data-id="427083"> <i class="iconfont icon-svgmoban53"></i> 讨论(0) </span> <div class="jieda-admin"> </div> </div> <div class="comments-mod " style="display: none; float:none;padding-top:10px;" id="comment_427083"> <div class="areabox clearfix"> <form class="layui-form" action=""> <div class="layui-form-item"> <label class="layui-form-label" style="padding-left:0px;width:60px;">发布评论:</label> <div class="layui-input-block" style="margin-left:90px;"> <input type="text" placeholder="不少于5个字" AUTOCOMPLETE="off" class="comment-input layui-input" name="content" /> <input type='hidden' value='0' name='replyauthor' /> </div> <div class="mar-t10"><span class="fr layui-btn layui-btn-sm addhuidapinglun" data-id="427083">提交评论 </span></div> </div> </form> </div> <hr> <ul class="my-comments-list nav"> <li class="loading"> <img src='https://www.e-learn.cn/qa/static/css/default/loading.gif' align='absmiddle' /> 加载中... </li> </ul> </div> </li> <li data-id="111"> <a name="item-1111111111"></a> <div class="detail-about detail-about-reply"> <a class="fly-avatar" href="https://www.e-learn.cn/qa/u-105.html"> <img src="https://www.e-learn.cn/qa/data/avatar/000/00/01/small_000000105.jpg" alt=" "> </a> <div class="fly-detail-user"> <a href="https://www.e-learn.cn/qa/u-105.html" class="fly-link"> <cite>逝去的感伤 </cite> </a> </div> <div class="detail-hits"> <span>2020-11-27 08:36</span> </div> </div> <div class="detail-body jieda-body photos"> <p>This is from Google - best practices - "Minimize payload size" https://developers.google.com/speed/docs/best-practices/payload (my emphasis)</p> <p>To ensure that your content compresses well, do the following: ... <em>Use consistent quoting for HTML tag attributes, i.e. always single quote, always double quote, <strong>or no quoting at all</strong> where possible.</em></p> <div class="appendcontent"> </div> </div> <div class="jieda-reply"> <span class="jieda-zan button_agree" type="zan" data-id='427086'> <i class="iconfont icon-zan"></i> <em>0</em> </span> <span type="reply" class="showpinglun" data-id="427086"> <i class="iconfont icon-svgmoban53"></i> 讨论(0) </span> <div class="jieda-admin"> </div> </div> <div class="comments-mod " style="display: none; float:none;padding-top:10px;" id="comment_427086"> <div class="areabox clearfix"> <form class="layui-form" action=""> <div class="layui-form-item"> <label class="layui-form-label" style="padding-left:0px;width:60px;">发布评论:</label> <div class="layui-input-block" style="margin-left:90px;"> <input type="text" placeholder="不少于5个字" AUTOCOMPLETE="off" class="comment-input layui-input" name="content" /> <input type='hidden' value='0' name='replyauthor' /> </div> <div class="mar-t10"><span class="fr layui-btn layui-btn-sm addhuidapinglun" data-id="427086">提交评论 </span></div> </div> </form> </div> <hr> <ul class="my-comments-list nav"> <li class="loading"> <img src='https://www.e-learn.cn/qa/static/css/default/loading.gif' align='absmiddle' /> 加载中... </li> </ul> </div> </li> <style> .laypage-main a, .laypage-main span { display: inline-block; } </style> </ul> <div class="layui-form layui-form-pane"> <form id="huidaform" name="answerForm" method="post"> <div class="layui-form-item layui-form-text"> <a name="comment"></a> <div class="layui-input-block"> <script type="text/javascript" src="https://www.e-learn.cn/qa/static/js/neweditor/ueditor.config.js"></script> <script type="text/javascript" src="https://www.e-learn.cn/qa/static/js/neweditor/ueditor.all.js"></script> <script type="text/plain" id="editor" name="content" style="width:100%;height:200px;"></script> <script type="text/javascript"> var isueditor=1; var editor = UE.getEditor('editor',{ //这里可以选择自己需要的工具按钮名称,此处仅选择如下五个 toolbars:[['source','fullscreen', '|', 'undo', 'redo', '|', 'bold', 'italic', 'underline', 'fontborder', 'strikethrough', 'removeformat', 'formatmatch', 'autotypeset', 'blockquote', 'pasteplain', '|', 'forecolor', 'backcolor', 'insertorderedlist', 'insertunorderedlist', 'selectall', 'cleardoc', '|', 'rowspacingtop', 'rowspacingbottom', 'lineheight', '|', 'customstyle', 'paragraph', 'fontfamily', 'fontsize', '|', 'indent', '|', 'justifyleft', 'justifycenter', 'justifyright', 'justifyjustify', '|', 'link', 'unlink', 'anchor', '|', 'simpleupload', 'insertimage', 'scrawl', 'insertvideo', 'attachment', 'map', 'insertcode', '|', 'horizontal', '|', 'preview', 'searchreplace', 'drafts']], initialContent:'', //关闭字数统计 wordCount:false, zIndex:2, //关闭elementPath elementPathEnabled:false, //默认的编辑区域高度 initialFrameHeight:250 //更多其他参数，请参考ueditor.config.js中的配置项 //更多其他参数，请参考ueditor.config.js中的配置项 }); editor.ready(function() { editor.setDisabled(); }); $("#editor").find("*").css("max-width","362px"); </script> </div> </div> <div class="layui-form-item"> <label for="L_vercode" class="layui-form-label">验证码</label> <div class="layui-input-inline"> <input type="text" id="code" name="code" value="" required lay-verify="required" placeholder="图片验证码" autocomplete="off" class="layui-input"> </div> <div class="layui-form-mid"> <span style="color: #c00;"><img class="hand" src="https://www.e-learn.cn/qa/user/code.html" onclick="javascript:updatecode();" id="verifycode"><a class="changecode" href="javascript:updatecode();"> 看不清?</a></span> </div> </div> <div class="layui-form-item"> <input type="hidden" value="105295" id="ans_qid" name="qid"> <input type="hidden" id="tokenkey" name="tokenkey" value=''/> <input type="hidden" value="HTML attribute with/without quotes" id="ans_title" name="title"> <div class="layui-btn layui-btn-disabled" id="ajaxsubmitasnwer" >提交回复</div> </div> </form> </div> </div> <input type="hidden" value="105295" id="adopt_qid" name="qid" /> <input type="hidden" id="adopt_answer" value="0" name="aid" /> </div> <div class="layui-col-md4"> <!-- 热门讨论问题 --> <dl class="fly-panel fly-list-one"> <dt class="fly-panel-title">热议问题</dt> <!-- 本周热门讨论问题显示10条-->
