Knowledge Base

ACC: IsDate() Returns False with Date in Long Date Format

Article ID: 175385

Article Last Modified on 1/22/2007

Microsoft Access 1.0 Standard Edition
Microsoft Access 1.1 Standard Edition
Microsoft Access 2.0 Standard Edition
Microsoft Access 95 Standard Edition
Microsoft Access 97 Standard Edition

This article was previously published under Q175385

Moderate: Requires basic macro, coding, and interoperability skills.

SYMPTOMS

When you use the IsDate() function with a date in Long Date format, the function returns a value of False. For example, the following expression returns a value of False:

   IsDate("Thursday, January 1, 1998")

However, the following expression returns a value of True:

   IsDate("January 1, 1998")

CAUSE

The IsDate() function does not recognize days of the week; therefore, it does not recognize a date that is in Long Date format.

RESOLUTION

Do not use a date in Long Date format with the IsDate() function. If you want to verify the correct weekday for a particular date, use the Format() function to show the weekday. For example, the expression

Format("1/10/98","DDDD, MMMM D, YYYY")

returns the value

Saturday, January 10, 1998

MORE INFORMATION

Steps to Reproduce Behavior

Start Microsoft Access.
If you are using Microsoft Access version 7.0 or later, press CTRL+G to open the Debug window. If you are using Microsoft Access 2.0, follow these steps to open the Immediate window:
1. Open any database.
2. Click the Module tab, and then click New.
3. On the View menu, click Immediate Window.
Type the following expression, and then press ENTER:

?IsDate("Tuesday, January 01, 1991")

If you are using Microsoft Access version 7.0 or later, the function returns a value of False to the Debug window. If you are using Microsoft Access 2.0, the function returns a value of 0 to the Immediate window.

REFERENCES

For more information about the IsDate() function, search the Help Index for "IsDate function."

For more information about the Format() function, search the Help Index for "Format function."

Additional query words: cardinal days

Keywords: kbprb kbprogramming KB175385