Summary
Put a value into a string. Use the IsNumeric()
function.
Situation
You want to check whether a value is a valid number.
Needs
A value to check.
Provides
A variable that you know is a number.
Action
Put the value you want to check into a string. For example, suppose we wanted to check whether user input for number of goats is a number:
- Dim tInputValue As String
- Dim sNumberOfGoats As Single
- 'Get a value from the user (or a file, a cell, whatevs).
- tInputValue = InputBox("How many goats?")
- 'Test whether the value is numeric.
- If Not IsNumeric(tInputValue) Then
- 'Do something when the value is not numeric. E.g.:
- MsgBox "Sorry, number of goats must be a number."
- End
- End If
- 'Know that tInputValue has a number.
- 'This is safe:
- sNumberOfGoats = tInputValue
This is part of numeric field validation. It's often combined with a range check.
Where referenced