Date.parse Function (JavaScript)

The required dateVal argument is either a string containing a date or a VT_DATE value retrieved from an ActiveX object or other object. For information about date strings that the Date.parse function can parse. see Date and Time Strings (JavaScript).

The Date.parse function returns an integer value representing the number of milliseconds between midnight, January 1, 1970 and the date supplied in dateVal.

The following example illustrates the use of the Date.parse function.

var dateString = "November 1, 1997 10:15 AM";
var mSec = Date.parse(dateString);
document.write(mSec);
// Output: 878404500000

The following example returns the difference between the date provided and 1/1/1970.

var minMilli = 1000 * 60;    
var hrMilli = minMilli * 60;
var dyMilli = hrMilli * 24;

var ms = Date.parse(new Date("June 1, 1990"));
var days = Math.round(ms / dyMilli);

var dateStr = "";
dateStr += "There are " + days + " days ";
dateStr += "between 01/01/1970 and " + testDate;
document.write(dateStr);

// Output: There are 7456 days between 01/01/1970 and Fri Jun 1 00:00:00 PDT 1990

Supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards. Also supported in Windows Store apps. See Version Information.

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