String.StartsWith Method (String, Boolean, CultureInfo)
Determines whether the beginning of this string instance matches the specified string when compared using the specified culture.
Assembly: mscorlib (in mscorlib.dll)
Public Function StartsWith ( value As String, ignoreCase As Boolean, culture As CultureInfo ) As Boolean
Parameters
- value
-
Type:
System.String
The string to compare.
- ignoreCase
-
Type:
System.Boolean
true to ignore case during the comparison; otherwise, false.
- culture
-
Type:
System.Globalization.CultureInfo
Cultural information that determines how this string and value are compared. If culture is null, the current culture is used.
Return Value
Type: System.Booleantrue if the value parameter matches the beginning of this string; otherwise, false.
| Exception | Condition |
|---|---|
| ArgumentNullException | value is null. |
This method compares the value parameter to the substring at the beginning of this string that is the same length as value, and returns a value that indicates whether they are equal. To be equal, value must be an empty string (String.Empty), must be a reference to this same instance, or must match the beginning of this instance.
This method performs a comparison using the specified casing and culture.
The following example determines whether a string occurs at the beginning of another string. The StartsWith method is called several times using case sensitivity, case insensitivity, and different cultures that influence the results of the search.
' This code example demonstrates the ' System.String.StartsWith(String, ..., CultureInfo) method. Imports System Imports System.Threading Imports System.Globalization Class Sample Public Shared Sub Main() Dim msg1 As String = "Search for the target string ""{0}"" in the string ""{1}""." & vbCrLf Dim msg2 As String = "Using the {0} - ""{1}"" culture:" Dim msg3 As String = " The string to search ends with the target string: {0}" Dim result As Boolean = False Dim ci As CultureInfo ' Define a target string to search for. ' U+00c5 = LATIN CAPITAL LETTER A WITH RING ABOVE Dim capitalARing As String = "Å" ' Define a string to search. ' The result of combining the characters LATIN SMALL LETTER A and COMBINING ' RING ABOVE (U+0061, U+030a) is linguistically equivalent to the character ' LATIN SMALL LETTER A WITH RING ABOVE (U+00e5). Dim aRingXYZ As String = "å" & "xyz" ' Clear the screen and display an introduction. Console.Clear() ' Display the string to search for and the string to search. Console.WriteLine(msg1, capitalARing, aRingXYZ) ' Search using English-United States culture. ci = New CultureInfo("en-US") Console.WriteLine(msg2, ci.DisplayName, ci.Name) Console.WriteLine("Case sensitive:") result = aRingXYZ.StartsWith(capitalARing, False, ci) Console.WriteLine(msg3, result) Console.WriteLine("Case insensitive:") result = aRingXYZ.StartsWith(capitalARing, True, ci) Console.WriteLine(msg3, result) Console.WriteLine() ' Search using Swedish-Sweden culture. ci = New CultureInfo("sv-SE") Console.WriteLine(msg2, ci.DisplayName, ci.Name) Console.WriteLine("Case sensitive:") result = aRingXYZ.StartsWith(capitalARing, False, ci) Console.WriteLine(msg3, result) Console.WriteLine("Case insensitive:") result = aRingXYZ.StartsWith(capitalARing, True, ci) Console.WriteLine(msg3, result) End Sub 'Main End Class 'Sample ' 'Note: This code example was executed on a console whose user interface 'culture is "en-US" (English-United States). ' 'Search for the target string "Å" in the string "a°xyz". ' 'Using the English (United States) - "en-US" culture: 'Case sensitive: ' The string to search ends with the target string: False 'Case insensitive: ' The string to search ends with the target string: True ' 'Using the Swedish (Sweden) - "sv-SE" culture: 'Case sensitive: ' The string to search ends with the target string: False 'Case insensitive: ' The string to search ends with the target string: False '
Available since 2.0