how to increase character limit for visual basic alert boxes

Question

I have the following code:

If Not strValidate ="" Then
    alert("The following information is required:" + vbLf + strValidate) 
    ValidateDocument = False
    Exit Function
End If

The variable "strValidate" contains a long number of characters, so when the alert box shows, it doesn't show the whole string, the remaining characters are cut off on the alert box.