Microsoft Office 2000/Visual Basic Programmer's Guide

String Operations

The following points provide suggestions for ways to enhance the performance of string operations:

Minimize concatenation operations when you can. You can use the Mid function on the left side of the equal sign to replace characters within the string, rather than concatenating them together. The drawback to using the Mid function is that the replacement string must be the same length as the substring you are replacing.
```
Dim strText As String

strText = "this is a test"
Mid(strText, 11, 4) = "tent"
Debug.Print strText
```
VBA provides a number of intrinsic string constants that you can use to replace function calls. For example, you can use the vbCrLf constant to represent a carriage return/linefeed combination within a string, rather than using Chr(13) & Chr(10).
String-comparison operations are slow. You can sometimes avoid them by converting a character in the string to an ANSI value. For example, this code checks whether the first character in a string is a space:
```
If Asc(strText) = 32 Then
```
The previous code is faster than the following:
```
If Left(strText, 1) = " " Then
```