1 <!DOCTYPE html> 2 <html xmlns="http://www.w3.org/1999/xhtml"> 3 <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 5 <title></title> 6 <script src="jq/jquery-3.0.0.min.js"></script> 7 </head> 8 <body> 9 <input type="text" value="" id="a1" /> 10 <input type="text" value="" id="a2" /> 11 <input type="text" value="" id="a3" /> 12 <input type="text" value="" id="a4" /> 13 <input type="button" value="确定" id="a5" /> 14 <script> 15 $(document).ready(function () { 16 $("input[type='button']").click(function () { 17 //alert("为空") 18 //数组 19 var num = $("input[type='text']"); 20 var aaa = ""; 21 for (var i = 0; i < num.length; i++) { 22 if (num.eq(i).val() == "") { 23 aaa += "第" + i + "个文本框为空"; 24 //a+=b 相当于 a = a+b 25 } 26 } 27 alert(aaa); 28 }); 29 }); 30 </script> 31 </body> 32 </html>