Guest Author - Lisa Shea

It's important to test that your data is valid before you work with it. These variable testing functions do the trick!

IsArray Function
IsArray lets you know if you can do array functions on the variable.

IsDate Function
IsDate can be CRITICAL before you try to store a variable in a database - otherwise the database will choke on the row.

IsEmpty Function
IsEmpty lets you know if the variable has been initialized.

IsNull Function
Be sure to check for null values before you try to work with your variable.

IsNumeric Function
You'll want to be sure your variable has a numeric value before trying to add or subtract.

IsObject Function
IsObject will help you if you're doing work with OLE or ActiveX objects.

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