JavaScript Tutorial: A function to determine whether a date is correct or not

VBScript's IsDate function is used to determine whether a date is correct, JavaScript does not have this function, and we also write a similar function. It is important to note that isdate parameters in JavaScript must be strings and support 6 different formats "YYYY-MM-DD | | Yyyy/mm/dd | | dd-mm-yyyy | | dd/mm/yyyy | | mm-dd-yyyy | | Mm/dd/yyyy ", the reason why you can't use a date as a parameter is because JavaScript doesn't have an incorrect date, such as new Date (2008,01,30), and the constructor automatically converts it to the correct date 2008-03-01. The JavaScript version IsDate function is as follows:

Function IsDate (dateval) {
    var arr = new Array ();
   
     if (Dateval.indexof ("-")!=-1) {
        arr = dateval.tostring (). Split ( "-");
   }else if (Dateval.indexof ("/")!=-1) {
        arr = Dateval.tostring (). Split ("/");
   }else{
        return false;
   }
   
   //yyyy-mm-dd | | yyyy/mm/dd
    if (arr[0].length==4) {
        var date = new Date (arr[0],arr[1]-1,arr[2]);
        if (Date.getfullyear () ==arr[0] && date.getmonth () ==arr[1]-1 && date.getdate () ==arr[2]) {
            return True
       }

}
dd-mm-yyyy | | Dd/mm/yyyy
if (arr[2].length==4) {
var date = new Date (arr[2],arr[1]-1,arr[0]);
if (Date.getfullyear () ==arr[2] && date.getmonth () ==arr[1]-1 && date.getdate () ==arr[0]) {
return true;
}
}
mm-dd-yyyy | | Mm/dd/yyyy
if (arr[2].length==4) {
var date = new Date (arr[2],arr[0]-1,arr[1]);
if (Date.getfullyear () ==arr[2] && date.getmonth () ==arr[0]-1 && date.getdate () ==arr[1]) {
return true;
}
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return false;
}