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This time I will bring you jqueryHow to determine whether the element content is empty, jquery determines whether the element content is emptyWhat are the precautions, the following is a practical case, let's take a look .
Using jquery to obtain element content requires two situations:
Input uses val();
var value = $('#test' ).val();
How to determine whether it is empty:
if(value.length == 0){} Operation performed if value is empty
if (value!=''){} Operations performed if value is not empty
jQuery verifies that the content of the text box is not empty
Extended jQuery method through $.fn
/** * 校验文本是否为空 * tips:提示信息 * 使用方法:$("#id").validate("提示文本"); * @itmyhome */ $.fn.validate = function(tips){ if($(this).val() == "" || $.trim($(this).val()).length == 0){ alert(tips + "不能为空!"); throw SyntaxError(); //如果验证不通过,则不执行后面 } }
html elementUse html();
var value = $('#test').html();
How to judge whether it is empty:
if(value.length == 0){
You can also judge whether there are any child nodes? For the method of html acquisition,
$('#list').children().length === 0 is available.
Method 1
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Method 2,
String.prototype.isEmpty = function () { var s1 = this.replace(/[\r\n]/g, '').replace(/[ ]/g, ''), s2 = (s1 == '') ? true : false; return s2; }; $list.html().isEmpty();
if( $("#list").html() === "" ){} Use three etc. The number is more in line with
. I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
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How to use Vue to implement a floating/hidden menu in the upper right corner of the page
How to use vue mint -ui tabbar (with code)
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