How to validate time format from a text field?

[wdsnews]

The goal is to normalize data before converting text fields to datetime
fields.

There are start times and end times stored in text fields of a table. The
problem is that any criteria used in a query causes errors when any function
causes text to be converted to a datetime type, and the text field does not
contain a valid date or time.

I'm familiar with some of the validation functions such as isNull(), but I
can't find anything like isTime(). How can I test existing data for valid
time format?

 

[Douglas J. Steele]

IsDate works on time as well.

 

[WDSnews]

thank you

IsDate works on time as well.