Monday, April 19, 2021

Mid function

Returns a Variant (String) containing a specified number of characters from a string.

Syntax

Mid( string, start [, length ] )

The Mid function syntax has these arguments:

Argument

Description

string

Required. string expression from which characters are returned. If string contains Null, Null is returned.

start

Required. Long. Character position in string at which the part to be taken begins. If start is greater than the number of characters in string, Mid returns a zero-length string ("").

length

Optional. Variant (Long). Number of characters to return. If omitted or if there are fewer than length characters in the text (including the character at start), all characters from the start position to the end of the string are returned.


Remarks

To determine the number of characters in string, use the Len function.

Note: Use the MidB function with byte data contained in a string, as in double-byte character set languages. Instead of specifying the number of characters, the arguments specify numbers of bytes. For sample code that uses MidB, see the second example in the example topic.

Query examples

Expression

Results

SELECT ProductID, Mid(ProductID,5) AS Expr1 FROM ProductSales;

Returns the "ProductID" and the part of ProductID starting from character position 5 and displays the results in the column Expr1.

SELECT ProductID, Mid(ProductID,5,4) AS testMid FROM ProductSales;

Returns the "ProductID" and the part of ProductID starting from character position 5, containing 4 characters and displays the results in the column testMid.

VBA examples

Note: Examples that follow demonstrate the use of this function in a Visual Basic for Applications (VBA) module. For more information about working with VBA, select Developer Reference in the drop-down list next to Search and enter one or more terms in the search box.

The first example uses the Mid function to return a specified number of characters from a string.

Dim MyString, FirstWord, LastWord, MidWords
MyString = "Mid Function Demo" ' Create text string.
FirstWord = Mid(MyString, 1, 3) ' Returns "Mid".
LastWord = Mid(MyString, 14, 4) ' Returns "Demo".
MidWords = Mid(MyString, 5) ' Returns "Function Demo".

The second example use MidB and a user-defined function (MidMbcs) to also return characters from string. The difference here is that the input string is ANSI and the length is in bytes.

Function MidMbcs(ByVal str as String, start, length)
MidMbcs = StrConv(MidB(StrConv(str, vbFromUnicode), _
start, length), vbUnicode)
End Function
Dim MyString
MyString = "AbCdEfG"
' Where "A", "C", "E", and "G" are DBCS and "b", "d",
' and "f" are SBCS.
MyNewString = Mid(MyString, 3, 4)
' Returns ""CdEf"
MyNewString = MidB(MyString, 3, 4)
' Returns ""bC"
MyNewString = MidMbcs(MyString, 3, 4)
' Returns "bCd"

See Also

String functions and how to use them

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