Flex String to Date

http://hi.baidu.com/lushaofeng21/blog/item/0aaf8ffba5785b1b6c22eb37.html

 

 

 

 写道

have been trying to find a really fast way to parse yyyy-mm-dd [hh:mm:ss] into a Date object. Here are the 3 ways I have tried doing it and the times it takes each method to parse 50,000 date time strings.
Does anyone know any faster ways of doing this or tips to speed up the methods?

castMethod1 takes 3673 ms
castMethod2 takes 3812 ms
castMethod3 takes 3931 ms

private function castMethod1(dateString:String):Date { 
    if ( dateString == null ) { 
        return null; 
    } 
 
    var year:int = int(dateString.substr(0,4)); 
    var month:int = int(dateString.substr(5,2))-1; 
    var day:int = int(dateString.substr(8,2)); 
 
    if ( year == 0 && month == 0 && day == 0 ) { 
        return null; 
    } 
 
    if ( dateString.length == 10 ) { 
        return new Date(year, month, day); 
    } 
 
    var hour:int = int(dateString.substr(11,2)); 
    var minute:int = int(dateString.substr(14,2)); 
    var second:int = int(dateString.substr(17,2)); 
 
    return new Date(year, month, day, hour, minute, second); 
} 
-

private function castMethod2(dateString:String):Date { 
    if ( dateString == null ) { 
        return null; 
    } 
 
    if ( dateString.indexOf("0000-00-00") != -1 ) { 
        return null; 
    } 
 
    dateString = dateString.split("-").join("/"); 
 
    return new Date(Date.parse( dateString )); 
} 
-

private function castMethod3(dateString:String):Date { 
    if ( dateString == null ) { 
        return null; 
    } 
 
    var mainParts:Array = dateString.split(" "); 
    var dateParts:Array = mainParts[0].split("-"); 
 
    if ( Number(dateParts[0])+Number(dateParts[1])+Number(dateParts[2]) == 0 ) { 
        return null; 
    } 
 
    return new Date( Date.parse( dateParts.join("/")+(mainParts[1]?" "+mainParts[1]:" ") ) ); 
}