jquery判断元素内容是否为空的方法 原创

/** * 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  }}

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String.prototype.isEmpty = function () { var s1 = this.replace(/[/r/n]/g, '').replace(/[ ]/g, ''),   s2 = (s1 == '') ? true : false; return s2;};$list.html().isEmpty();