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Replaces a specified number of characters in a String variable with characters from another string.
Mid( _ ByRef Target As String, _ ByVal Start As Integer, _ Optional ByVal Length As Integer _ ) = StringExpression
Required. Name of the String variable to modify.
Required. Integer expression. Character position in Target where the replacement of text begins. Start uses a one-based index.
Optional. Integer expression. Number of characters to replace. If omitted, all of String is used.
Required. String expression that replaces part of Target.
|Exception type||Error number||Condition|
Start <= 0 or Length < 0.
See the "Error number" column if you are upgrading Visual Basic 6.0 applications that use unstructured error handling. (You can compare the error number against the.) However, when possible, you should consider replacing such error control with .
The number of characters replaced is always less than or equal to the number of characters in Target.
Visual Basic has aand a Mid statement. These elements both operate on a specified number of characters in a string, but the Mid function returns the characters while the Mid statement replaces the characters. For more information, see .
The MidB statement of earlier versions of Visual Basic replaces a substring in bytes, rather than characters. It is used primarily for converting strings in double-byte character set (DBCS) applications. All Visual Basic strings are in Unicode, and MidB is no longer supported.
This example uses the Mid statement to replace a specified number of characters in a string variable with characters from another string.
Dim TestString As String ' Initializes string. TestString = "The dog jumps" ' Returns "The fox jumps". Mid(TestString, 5, 3) = "fox" ' Returns "The cow jumps". Mid(TestString, 5) = "cow" ' Returns "The cow jumpe". Mid(TestString, 5) = "cow jumped over" ' Returns "The duc jumpe". Mid(TestString, 5, 3) = "duck"
Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)