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Option Compare Statement
Declares the default comparison method to use when comparing string data.
If used, the Option Compare statement must appear in a file before any other source code statements.
The Option Compare statement specifies the string comparison method (Binary or Text) for a class, module, or structure. If an Option Compare statement is not included, the default text comparison method is Binary.
In Microsoft Windows, sort order is determined by the code page. For more information, see Code Pages.
In the following example, characters in the English/European code page (ANSI 1252) are sorted by using Option Compare Binary, which produces a typical binary sort order.
A < B < E < Z < a < b < e < z < À < Ê < Ø < à < ê < ø
When the same characters in the same code page are sorted by using Option Compare Text, the following text sort order is produced.
(A=a) < (À = à) < (B=b) < (E=e) < (Ê = ê) < (Z=z) < (Ø = ø)
You can also set Option Compare in the Visual Studio integrated development environment (IDE) or on a command line.
The dialog boxes and menu commands you see might differ from those described in Help, depending on your active settings or edition. To change your settings, click Import and Export Settings on the Tools menu. For more information, see Visual Studio Settings.
To set Option Compare in the IDE
On the Tools menu, click Options.
Open the Projects and Solutions node.
Choose VB Defaults.
Modify the Option Compare setting.
To set Option Compare on the command line
Include the /optioncompare compiler option in the vbc command.
The following example uses the Option Compare statement to set the binary comparison as the default string comparison method.
The following example uses the Option Compare statement to set the case-insensitive text sort order as the default string comparison method.