Javascript：检查页面是否包含特定的 div
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Javascript: Check if page contains a particular div
提问by Skizit
How do I check using javascript if the page I'm on contains a particular div... e.g turtles
如果我所在的页面包含特定的 div，我如何使用 javascript 检查...例如 turtles
回答by niksvp
if(document.getElementById("divid")!=null){
alert('Div exists')
}
回答by BiAiB
if you have that div's id, you can do it that way:
如果你有那个 div 的 id，你可以这样做：
var myDiv = document.getElementById( 'turtles' );
if ( myDiv ) {
//It exists
}
overwise, if it's a class, you'd better use a framework (jQuery here):
过度，如果它是一个类，你最好使用一个框架（这里是 jQuery）：
if ( $('.turtles').length > 0 ) {
//it exists
}
回答by Elliot B.
I'd just like to point out that document.containsis another way to do this.
我只想指出document.contains是另一种方法。
document.containsis particularly useful if you have a web application whose components are rendered virtually before insertion into the DOM.
document.contains如果您有一个 Web 应用程序，其组件在插入 DOM 之前已虚拟呈现，则此方法特别有用。
回答by Shadow Wizard is Ear For You
Like this:
像这样：
<script type="text/javascript">
function CheckExists() {
var oDiv = document.getElementById("turtles");
if (oDiv) {
alert("exists");
}
else {
alert("does not exist");
}
}
</script>
The function must be located in bottom of page or called after page finished loading.
该函数必须位于页面底部或在页面加载完成后调用。
