Numeric amount plus comma; JS two methods of adding three digits and a comma to numbers; JS data formatting

demand ： Digital amount , Display three digits with a comma . Both thousand One million One billion
Or it can be displayed with a comma according to a fixed number of digits .

Method 1：

<script  type= "text/javascript">
   // Keep three decimal places ,toLocaleString()  The method can put a  Number  Object to a string in local format .
    var   num_s = "1232134456.546 ";
    alert(parseFloat(num_s).toLocaleString());
 
</script>

Method 2： After the decimal point 00 The display is also saved

<script type="text/javascript">//  There is no limit to the number of decimal places 
    function format_number(nStr ){
    
        nStr += '';  
        x = nStr.split('.');  
        x1 = x[0];  
        x2 = x.length > 1 ? '.' + x[1] : '';  
        var rgx = /(\d+)(\d{3})/;   //3 Is the number of digits in the interval 
        while (rgx.test(x1)) {
      
            x1 = x1.replace(rgx, '$1' + ',' + '$2');  
        }  
        return x1 + x2;  
    }
 
    var a="53669988.000";
    alert(format_number(a));
    alert(format_number("wahh"));
    alert(format_number(0));
    alert(format_number(6698.0023));
</script>