1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>format-number</title> 6 </head> 7 <body> 8 <input type="text" id="input"><input type="text" id="output"> 9 </body> 10 <script> 11 var ipt=document.getElementById(‘input‘); 12 var opt=document.getElementById(‘output‘); 13 ipt.oninput=function(){ 14 opt.value=zero(this.value); 15 } 16 function zero(num){ 17 var str=num.toString(); 18 if(str.indexOf(".")==-1){ 19 return num+".00"; 20 }else{ 21 var len=str.indexOf("."); 22 if(str.slice(str.indexOf(‘.‘)).length == 2){ 23 return num+"0" 24 }else if(str.slice(str.indexOf(‘.‘)).length > 3){ 25 var len=str.indexOf("."); 26 var str1=str.slice(0,len); 27 var leng=str1.length+3; 28 var str2=str.slice(0,leng); 29 return Number(str2); 30 }else{ 31 return num; 32 } 33 } 34 } 35 </script> 36 </html>