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Mid Statement

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

Parts

  • Target
    Required. Name of the String variable to modify.

  • Start
    Required. Integer expression. Character position in Target where the replacement of text begins. Start uses a one-based index.

  • Length
    Optional. Integer expression. Number of characters to replace. If omitted, all of String is used.

  • StringExpression
    Required. String expression that replaces part of Target.

Exceptions

Exception type

Condition

ArgumentException

Start <= 0 or Length < 0.

Remarks

The number of characters replaced is always less than or equal to the number of characters in Target.

Visual Basic has a Mid function and 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 Mid.

Note

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.

Example

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"

Requirements

Namespace: Microsoft.VisualBasic

Module: Strings

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

See Also

Reference

Mid

Other Resources

Strings in Visual Basic

Introduction to Strings in Visual Basic