String.StartsWith Method (String)

Determines whether the beginning of this instance matches the specified string.

Namespace: System
Assembly: mscorlib (in mscorlib.dll)

'Declaration
Public Function StartsWith ( _
	value As String _
) As Boolean
'Usage
Dim instance As String
Dim value As String
Dim returnValue As Boolean

returnValue = instance.StartsWith(value)
public boolean StartsWith (
	String value
)
public function StartsWith (
	value : String
) : boolean
Not applicable.

Parameters

value

The String to compare.

Return Value

true if value matches the beginning of this string; otherwise, false.

Exception typeCondition

ArgumentNullException

value is a null reference (Nothing in Visual Basic).

This method compares value to the substring at the beginning of this instance that is the same length as value, and returns an indication whether they are equal. To be equal, value must be an empty string (Empty), a reference to this same instance, or match the beginning of this instance.

This method performs a word (case-sensitive and culture-sensitive) comparison using the current culture.

The following code example demonstrates how you can use the StartsWith method.

Imports System

Public Class EndsWithTest

    Public Shared Sub Main()
        Dim strSource As String() = {"<b>This is bold text</b>", _
                    "<H1>This is large Text</H1>", _
                    "<b><i><font color = green>This has multiple tags</font></i></b>", _
                    "<b>This has <i>embedded</i> tags.</b>", _
                    "<This line simply begins with a lesser than symbol, it should not be modified"}

        ' process a string that contains html tags
        ' this sample does not remove embedded tags (tags in the middle of a line)

        Console.WriteLine("The following lists the items before the tags have been stripped:")
        Console.WriteLine("-----------------------------------------------------------------")

        ' print out the initial array of strings
        Dim s As String
        For Each s In  strSource
            Console.WriteLine(s)
        Next s

        Console.WriteLine()

        Console.WriteLine("The following lists the items after the tags have been stripped:")
        Console.WriteLine("----------------------------------------------------------------")

        ' print out the array of strings
        For Each s In  strSource
            Console.WriteLine(StripStartTags(s))
        Next s

    End Sub 'Main

    Private Shared Function StripStartTags(item As String) As String

        ' try to find a tag at the start of the line using StartsWith
        If item.Trim().StartsWith("<") Then

            ' now search for the closing tag...
           Dim lastLocation As Integer = item.IndexOf(">")

            If lastLocation >= 0 Then
                ' remove the identified section, if it is a valid region
                item = item.Substring((lastLocation + 1))
            End If
        End If

        Return item

    End Function 'StripStartTags

End Class 'EndsWithTest

import System.*;

public class EndsWithTest
{
    public static void main(String[] args)
    {
        // process a string that contains html tags
        // this sample does not remove embedded tags
        // (tags in the middle of a line)
        String strSource[] =  { "<b>This is bold text</b>",
            "<H1>This is large Text</H1>", 
            "<b><i><font color=green>This has multiple tags</font></i></b>",
            "<b>This has <i>embedded</i> tags.</b>",
            "<This line simply begins with a lesser than symbol," 
            + " it should not be modified" };

        Console.WriteLine("The following lists the items before" 
            + " the ends have been stripped:");
        Console.WriteLine("-------------------------------------" 
            + "----------------------------");
        // print out the initial array of strings
        for (int iCtr = 0; iCtr < strSource.get_Length(); iCtr++) {
            String s = strSource[iCtr];
            Console.WriteLine(s);
        }
        Console.WriteLine();

        Console.WriteLine("The following lists the items after" 
            + " the ends have been stripped:");
        Console.WriteLine("---------------------------------------" 
            + "-------------------------");
        // print out the array of strings
        for (int iCtr = 0; iCtr < strSource.get_Length(); iCtr++) {
            String s = strSource[iCtr];
            Console.WriteLine(StripStartTags(s));
        }
    } //main

    private static String StripStartTags(String item)
    {
        // try to find a tag at the start of the line using StartsWith
        if (item.Trim().StartsWith("<")) {
            // now search for the closing tag...
            int lastLocation = item.IndexOf(">");
            // remove the identified section, if it is a valid region
            if (lastLocation >= 0) {
                item = item.Substring(lastLocation + 1);
            }
        }
        return item;
    } //StripStartTags
} //EndsWithTest

import System;

public class EndsWithTest {
    public static function Main() : void {

        // process a string that contains html tags
        // this sample does not remove embedded tags (tags in the middle of a line)

        var strSource : String [] = [ "<b>This is bold text</b>", "<H1>This is large Text</H1>",
                "<b><i><font color=green>This has multiple tags</font></i></b>",
                "<b>This has <i>embedded</i> tags.</b>",
                "<This line simply begins with a lesser than symbol, it should not be modified" ];

        Console.WriteLine("The following lists the items before the tags have been stripped:");
        Console.WriteLine("-----------------------------------------------------------------");

        // print out the initial array of strings
        for( var i : int in strSource )
            Console.WriteLine( strSource[i] );

        Console.WriteLine();

        Console.WriteLine("The following lists the items after the tags have been stripped:");
        Console.WriteLine("----------------------------------------------------------------");

        // print out the array of strings
        for ( i in strSource )
            Console.WriteLine( StripStartTags( strSource[i] ) );
    }

    private static function StripStartTags( item : String ) : String  {

        // try to find a tag at the start of the line using StartsWith
        if (item.Trim().StartsWith("<")) {

            // now search for the closing tag...
            var lastLocation : int = item.IndexOf( ">" );

            // remove the identified section, if it is a valid region
            if ( lastLocation >= 0 )
                item =  item.Substring( lastLocation + 1 );
        }

        return item;
    }
}
EndsWithTest.Main();

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0

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