The jquery method to determine whether it is a number: first create a front-end code sample file; then use the "if(!isNaN(t)){...}" method to determine whether it is a number; finally output the judgment result: Can.
The operating environment of this tutorial: Windows 7 system, jquery version 1.10.0. This method is suitable for all brands of computers.
Recommended: "jquery Tutorial"
jQuery method to determine whether it is a number and convert number function
<script language="javascript"> var t=$("#id").val();//这个就是我们要判断的值了 if(!isNaN(t)){ alert("是数字"); }else{ alert("不全是数字"); } </script>
Attachment:
JavaScript Number() function
Number() function converts the value of the object into a number.
<script type="text/javascript"> var test1= new Boolean(true); var test2= new Boolean(false); var test3= new Date(); var test4= new String("999"); var test5= new String("999 888"); document.write(Number(test1)+ "<br />"); document.write(Number(test2)+ "<br />"); document.write(Number(test3)+ "<br />"); document.write(Number(test4)+ "<br />"); document.write(Number(test5)+ "<br />"); </script>
Output
1 0 1256657776588 999 NaN
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