ZeeGrid Control Message

ZGM_ISDATEVALID


ZGM_ISDATEVALID

An application sends a ZGM_ISDATEVALID message to test the validity of a date represented as a null-terminated character string.

ZGM_ISDATEVALID
wParam = 0;                          //not used; must be 0
lParam = (LPARAM) lpszString;        //pointer to string representation of a date

Parameters

lpszString
The value of lParam. A null-terminated string containing the text representation of a date. This text can be in many date formats. For example, the date 12/28/1958 could be represented in string form as '1958/12/28', '12/28/58', '12/28/1958', 'Dec 28, 1958', or 'December 28, 1958'

Valid dates range from 1/1/1600 to 12/31/9999.

This fuction also tests for a valid number of days for a given month.

Return Values

This message returns the julian date of the date represented in the text string in lParam if it is a valid date. If it is not a valid date, the message returns 0.

Copyright © 2002-2016 by David Hillard