比較日期 結束日期不能早于開始日期

01.function getUserWorkId(CreateTime,SolveTime)   
02.{     
03.      
04.       var DateOne = document.getElementById(CreateTime).value;   
05.       var DateTwo = document.getElementById(SolveTime).value;    
06.  
07.       var OneMonth = DateOne.substring(5,DateOne.lastIndexOf ('-'));          
08.       var OneDay = DateOne.substring(DateOne.length,DateOne.lastIndexOf ('-')+1);          
09.       var OneYear = DateOne.substring(0,DateOne.indexOf ('-'));       
10.      
11.       var TwoMonth = DateTwo.substring(5,DateTwo.lastIndexOf ('-'));          
12.       var TwoDay = DateTwo.substring(DateTwo.length,DateTwo.lastIndexOf ('-')+1);          
13.       var TwoYear = DateTwo.substring(0,DateTwo.indexOf ('-'));          
14.       var cha=((Date.parse(OneMonth+'/'+OneDay+'/'+OneYear)- Date.parse(TwoMonth+'/'+TwoDay+'/'+TwoYear))/86400000);    
15. if(DateTwo.length>0)   
16.       {   
17.         if(cha>0)   
18.         {   
19.            alert('計劃結束日期不能早于開始日期！');   
20.            return false;   
21.         }   
22.       }    
23.}