Share via

Strings.StrConv(String, VbStrConv, Int32) Method


Returns a string converted as specified.

public static string? StrConv (string? str, Microsoft.VisualBasic.VbStrConv Conversion, int LocaleID = 0);
public static string StrConv (string str, Microsoft.VisualBasic.VbStrConv Conversion, int LocaleID = 0);
static member StrConv : string * Microsoft.VisualBasic.VbStrConv * int -> string
static member StrConv : string * Microsoft.VisualBasic.VbStrConv * int -> string
Public Function StrConv (str As String, Conversion As VbStrConv, Optional LocaleID As Integer = 0) As String



Required. String expression to be converted.


Required. VbStrConv member. The enumeration value specifying the type of conversion to perform.


Optional. The LocaleID value, if different from the system LocaleID value. (The system LocaleID value is the default.)


A string converted as specified.



Unsupported LocaleID, Conversion < 0 or > 2048, or unsupported conversion for specified locale.


This example converts text into all lowercase letters.

Dim sText As String = "Hello World"
' Returns "hello world".
Dim sNewText As String = StrConv(sText, VbStrConv.LowerCase)


The constants VbStrConv.Wide, VbStrConv.Narrow, VbStrConv.SimplifiedChinese, VbStrConv.TraditionalChinese, VbStrConv.Katakana, and VbStrConv.Hiragana can cause run-time errors when used in locales where they do not apply, but not always: the constants VbStrConv.Katakana and VbStrConv.Hiragana can be used in a non-Japanese system with the Japanese Language Pack installed. In addition, use of the constants VbStrConv.Wide and VbStrConv.Narrow is supported on any system with an East Asian language installed.

This function uses the application's culture information when manipulating the string so that the case changes are appropriate for the locale in which the application is being used.


If your application makes security decisions based on the result of a comparison or case-change operation, then the operation should use the String.Compare method, and pass Ordinal or OrdinalIgnoreCase for the comparisonType argument. For more information, see How Culture Affects Strings in Visual Basic.

The Conversion argument settings are:

Enumeration member Description
VbStrConv.None Performs no conversion
VbStrConv.LinguisticCasing Uses linguistic rules for casing, rather than File System (default). Valid with VbStrConv.UpperCase and VbStrConv.LowerCase only.
VbStrConv.UpperCase Converts the string to uppercase characters.
VbStrConv.LowerCase Converts the string to lowercase characters.
VbStrConv.ProperCase Converts the first letter of every word in string to uppercase.
VbStrConv.Wide * Converts narrow (half-width) characters in the string to wide (full-width) characters. The conversion may use Normalization Form C even if an input character is already full-width. For example, the string "は゛" (which is already full-width) is normalized to "ば". See Unicode normalization forms.
VbStrConv.Narrow * Converts wide (full-width) characters in the string to narrow (half-width) characters.
VbStrConv.Katakana ** Converts Hiragana characters in the string to Katakana characters.
VbStrConv.Hiragana ** Converts Katakana characters in the string to Hiragana characters.
VbStrConv.SimplifiedChinese * Converts Traditional Chinese characters to Simplified Chinese.
VbStrConv.TraditionalChinese * Converts Simplified Chinese characters to Traditional Chinese.

* Applies to Asian locales.

** Applies to Japan only.


These constants are specified in the .NET Framework common language runtime. As a result, they can be used anywhere in your code in place of the actual values. Most can be combined (for example, UpperCase + Wide), except when they are mutually exclusive (for example, VbStrConv.Wide + VbStrConv.Narrow).

The following are valid word separators for proper casing: Null (Chr$(0)), horizontal tab (Chr$(9)), line feed (Chr$(10)), vertical tab (Chr$(11)), form feed (Chr$(12)), carriage return (Chr$(13)), space (single-byte character set) (Chr$(32)). The actual value for a space, which can be full or half width, varies by country/region for East Asian cultures.

Applies to

See also