"Can't Assign Array..." Passing Argument to Subroutine

• Microsoft Visual Basic Programming System, Applications Edition, version 1.0

SYMPTOMS

In Microsoft Visual Basic Programming System, Applications Edition, if you pass an argument to a subroutine and the argument data type does not match the parameter data type defined in the subroutine, you receive the following error message:

   Can't assign array of fixed-length string or user-defined type to
   Variant

MORE INFORMATION

Variant is a special data type that can contain any kind of data. You can determine how the data in a Variant is treated using the VarType or TypeName function. When you declare a variable as Variant data type, you can change the data type of the variable within a procedure. If the contents of a Variant variable are digits, they may be either the string representation of the digits or their actual value, depending on the context.

However, when you are passing a variable to a subroutine, the data type must match the data type of the subroutine parameter, even when the variable you are passing or the parameter declared in the subroutine is declared as Variant data type.

Visual Basic Example

When you run the procedure Run_Test below in a Visual Basic module in Microsoft Excel version 5.0, you receive the error message described above:

Dim x() As Label

Sub Run_Test()
   ' Pass variable x to Test subroutine
   Test x
End Sub

Sub Test(A As Variant)
     ' Resize array to one element
   ReDim A(0)
   ' Assign array value to label object on worksheet
   Set A(0)=ThisWorkbook.Worksheets("Sheet1").Labels.Add(10,10,75,16)
   ' Set name of label
   A(0).Name = "Label1"
   MsgBox TypeName(A(0))
End Sub

WORKAROUND

To avoid receiving this error message when you pass a variable to a subroutine, you must define the variable you are passing to the subroutine to be the same data type as the subroutine parameter.

To run the procedure in the above example without receiving the error message, modify the procedure as in the following examples:

Example 1

Dim x() As Label

Sub Run_Test()
   ' Pass variable x to Test subroutine
   Test x()
End Sub

Sub Test(A() As Label)
     ' Resize array to one element
   ReDim A(0)
   ' Assign array value to label object on worksheet
   Set A(0)=ThisWorkbook.Worksheets("Sheet1").Labels.Add(10,10,75,16)
   ' Set name of label
   A(0).Name = "Label1"
   MsgBox TypeName(A(0))
End Sub

Example 2

Dim x() As Variant

Sub Run_Test()
   ' Resize array to two elements
   Redim x(1)
   ' Assign first element in array to label object on worksheet
   Set x(0)=ThisWorkbook.Worksheets("Sheet1").Labels.Add(10,10,75,16)
   ' Pass variable x to Test subroutine
   Test x
End Sub

Sub Test(A As Variant)
   ' Assign second element in array to label object on worksheet
   Set A(1)=ThisWorkbook.Worksheets("Sheet1").Labels.Add(10,10,75,16)
   ' Set name of label
   A(1).Name = "Label1"
   MsgBox TypeName(A(1))
End Sub

REFERENCES

For more information about the Dim statement, choose the Search button in the Visual Basic Reference and type:

    Dim