XL98: No Automatic Type Coercion Between Variable Types

WORKAROUND

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The following workarounds assume that you have a Visual Basic module that contains two macros:

   Sub Macro1()
       Dim X As Variant
       X = ActiveWorkbook.Sheets("Sheet1").Range("A1:A5")
       Macro2 X(1, 1)          ' X is an array of type Variant...
   End Sub

   Sub Macro2(Y As Integer)    ' ...but Macro2 expects an Integer.
       MsgBox Y
   End Sub
				

When run, the first macro (Macro1) initializes an array named X, populates the array, and then sends a value from the array to the second macro (Macro2). Macro2 then displays the value in a message box. If you run Macro1 without applying any of the following workarounds, you will receive the error message mentioned in the "Symptoms" section.

Method 1

To prevent the problem from occurring, change how the second macro (Macro2) accepts values. In this case, change the second macro to

   Sub Macro2(Y As Variant)    ' Y is now a Variant, not an Integer.
       MsgBox Y
   End Sub
				

to eliminate the problem, because an element from an array of type Variant is being sent to a variable of type Variant.

Method 2

A second way to prevent the problem from occurring is to convert the value to an Integer as you pass it to the second macro using the CInt function.

   Sub Macro1()
       Dim X As Variant
       X = ActiveWorkbook.Sheets("Sheet1").Range("A1:A5")
       Macro2 CInt(X(1, 1))  ' Convert Variant X(1, 1) using Cint.
   End Sub

   Sub Macro2(Y As Integer)  ' Macro2 expects an Integer.
       MsgBox Y
   End Sub
				

Method 3

Another way to prevent the problem from occurring is to dimension a second variable in the first macro. This second variable should be of the same type as the value accepted by the second macro. The value from the array is copied into the second variable, which is then sent to the second macro. For example:

   Sub Macro1()
       ' Z is the second variable. It is an Integer, just like Y.
       Dim X As Variant, Z As Integer

       X = ActiveWorkbook.Sheets("Sheet1").Range("A1:A5")
       Z = X(1, 1) ' Get the value from the array and put it in Z.
       Macro2 Z    ' This works correctly.
   End Sub
				

Because Z is an Integer, the value of Z is received by Macro2 (which expects an Integer) correctly.