VB.Net by API/System/String — различия между версиями

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Версия 16:40, 26 мая 2010

String.Compare

  
Imports System
Imports System.Collections
Public Class MainClass
    
    Shared Sub Main()
             Dim s1 As String = "abcd"
             Dim s2 As String = "ABCD"
             Dim result As Integer 
             result = String.rupare(s1, s2)
             Console.WriteLine( _
               "compare s1: {0}, s2: {1}, result: {2}" _
               & Environment.NewLine, s1, s2, result)
             result = String.rupare(s1, s2, True)
             Console.WriteLine("Compare insensitive. result: {0}" _
                & Environment.NewLine, result)
   End Sub
End Class


String.Concat

  
Imports System
Imports System.Collections
Public Class MainClass
    
    Shared Sub Main()
             Dim s1 As String = "abcd"
             Dim s2 As String = "ABCD"
             " concatenation method
             Dim s3 As String = String.Concat(s1, s2)
             Console.WriteLine("s3 concatenated from s1 and s2: {0}", s3)
             " use the overloaded operator
             Dim s4 As String = s1 & s2
             Console.WriteLine("s4 concatenated from s1 & s2: {0}", s4)
   End Sub
End Class


String.Copy

  
Imports System
Imports System.Collections
Public Class MainClass
    
    Shared Sub Main()
             Dim s1 As String = "abcd"
             Dim s2 As String = "ABCD"
             Dim s3 As String = "Liberty Associates, Inc. provides "
             s3 = s3 & "custom .NET development"
             Dim s5 As String = String.Copy(s2)
             Console.WriteLine("s5 copied from s2: {0}", s5)

             Dim location As Integer = s3.IndexOf("provides")
             Dim s10 As String = s3.Insert(location, "usually ")
             Console.WriteLine("s10: {0}", s10)
   End Sub
End Class


String.Empty

  

Option Strict On
Public Module CommandTest
   Public Sub Main()
      Dim arguments As String = Command
      If arguments = String.Empty Then
         Console.WriteLine("An empty string.")
      Else
         " handle command line argument(s)
         Console.WriteLine("Command line: {0}", arguments)
      End If
   End Sub
End Module


String.Equals

  
Imports System
Imports System.Collections
Public Class MainClass
    
    Shared Sub Main()
             Dim s1 As String = "abcd"
             Dim s2 As String = "ABCD"
             " the String copy method
             Dim s5 As String = String.Copy(s2)
             Console.WriteLine("s5 copied from s2: {0}", s5)
             " copy with the overloaded operator
             Dim s6 As String = s5
             Console.WriteLine("s6 = s5: {0}", s6)
             " member method
             Console.WriteLine("Does s6.Equals(s5)?: {0}", s6.Equals(s5))
             " shared method
             Console.WriteLine("Does Equals(s6,s5)?: {0}", _
                String.Equals(s6, s5))
   End Sub
End Class


String.Format

  
 
Public Class Tester
    Public Shared Sub Main
        Console.WriteLine(String.Format( _
            "There are about {0} days in {1} years.", _
            365.25 * 3, 3, 17))
 
    End Sub
End Class


String.GetEnumerator

  

public class Test
   public Shared Sub Main
        Dim S As String = "Welcome to VB"
        Dim Enumerator As CharEnumerator = S.GetEnumerator
    
        While (Enumerator.MoveNext())
          Console.WriteLine(Enumerator.Current())
        End While
   End Sub
End class


String.GetHashCode()

  
 
public class Test
   public Shared Sub Main
    Dim Number As String
    Number = "4"
    Console.WriteLine(Integer.Parse(Number))
    Console.WriteLine(Number.GetHashCode())
   End Sub
End class


String.IndexOfAny(String sub)

  
Imports System
Public Class MainClass
   Shared Sub Main()
      Dim letters As String = "abcdefghijklmabcdefghijklm"
      Dim searchLetters As Char() = New Char() {"c"c, "a"c, "$"c}
      Console.WriteLine("IndexOfAny to find first occurrence of character in array")
      Console.WriteLine("First occurrence of ""c""," & _
        " ""a"" or ""$"" is located at " & _
        letters.IndexOfAny(searchLetters))
      Console.WriteLine("First occurrence of ""c"", ""a"" or " & _
         """$"" is located at " & _
         letters.IndexOfAny(searchLetters, 7))
      Console.WriteLine("First occurrence of ""c"", ""a"" or " & _
         """$"" is located at " & _
         letters.IndexOfAny(searchLetters, 20, 5))
   End Sub " Main
End Class


String.IndexOfAny(String sub, Int count)

  
Imports System
Public Class MainClass
   Shared Sub Main()
      Dim letters As String = "abcdefghijklmabcdefghijklm"
      Dim searchLetters As Char() = New Char() {"c"c, "a"c, "$"c}
      Console.WriteLine("IndexOfAny to find first occurrence of character in array")
      Console.WriteLine("First occurrence of ""c""," & _
        " ""a"" or ""$"" is located at " & _
        letters.IndexOfAny(searchLetters))
      Console.WriteLine("First occurrence of ""c"", ""a"" or " & _
         """$"" is located at " & _
         letters.IndexOfAny(searchLetters, 7))
      Console.WriteLine("First occurrence of ""c"", ""a"" or " & _
         """$"" is located at " & _
         letters.IndexOfAny(searchLetters, 20, 5))
   End Sub " Main
End Class


String.IndexOf(String substring)

  
Imports System
Imports System.Collections
Public Class MainClass
    
    Shared Sub Main()
             Dim s1 As String = "abcd"
             Dim s2 As String = "ABCD"
             Dim s3 As String = "Liberty Associates, Inc. provides "
             s3 = s3 & "custom .NET development"
             Dim s5 As String = String.Copy(s2)
             Console.WriteLine("s5 copied from s2: {0}", s5)

             Dim location As Integer = s3.IndexOf("provides")
             Dim s10 As String = s3.Insert(location, "usually ")
             Console.WriteLine("s10: {0}", s10)
   End Sub
End Class


String.Insert

  
Imports System
Imports System.Collections
Public Class MainClass
    
    Shared Sub Main()
             Dim s1 As String = "abcd"
             Dim s2 As String = "ABCD"
             Dim s3 As String = "Liberty Associates, Inc. provides "
             s3 = s3 & "custom .NET development"
             Dim s5 As String = String.Copy(s2)
             Console.WriteLine("s5 copied from s2: {0}", s5)

             Dim location As Integer = s3.IndexOf("provides")
             Dim s10 As String = s3.Insert(location, "usually ")
             Console.WriteLine("s10: {0}", s10)
   End Sub
End Class


String.IsNullOrEmpty

  
Option Strict On
Imports System.Collections.ObjectModel
Imports System.IO
Public Module FileSystem
   Public Sub Main()
      Dim dirPath As String = "c:\\"
      If String.IsNullOrEmpty(dirPath) Then Exit Sub
      If Not Directory.Exists(dirPath) Then Exit Sub
      
      Dim dirs As ReadOnlyCollection(Of String) = My.ruputer.FileSystem.GetDirectories(dirPath)
      For Each dir As String In dirs
         Dim dirInfo As DirectoryInfo = New DirectoryInfo(dir)
         Console.WriteLine("{0} : Created {1}", dirinfo.Name,dirInfo.CreationTime)
      Next
   End Sub
End Module


String.LastIndexOf

  
Imports System
Public Class MainClass
   Shared Sub Main()
      Dim letters As String = "abcdefghijklmabcdefghijklm"
      Dim searchLetters As Char() = New Char() {"c"c, "a"c, "$"c}
      Console.WriteLine("LastIndexOf to find a character in a string")
      Console.WriteLine("Last ""c"" is located at " & _
         "index " & letters.LastIndexOf("c"c))
      Console.WriteLine("Last ""a"" is located at index " & _
         letters.LastIndexOf("a"c, 25))
      Console.WriteLine("Last ""$"" is located at index " & _
         letters.LastIndexOf("$"c, 15, 5))
   End Sub " Main
End Class


String.PadLeft(Int length)

  

Public Class MainClass
   Public Shared Sub Main()
       "Strings
        Dim strConstant As String = "ABC"
        Dim strRepeat As New String("A"c, 20)
        Dim strMyString As String = "Hello World"

        Console.WriteLine(strMyString.PadLeft(30))
        Console.WriteLine(strMyString.PadLeft(20, "."c))
        
   End Sub
End Class


String.PadLeft(Int length, String char)

  
Public Class MainClass
   Public Shared Sub Main()
       "Strings
        Dim strConstant As String = "ABC"
        Dim strRepeat As New String("A"c, 20)
        Dim strMyString As String = "Hello World"

        Console.WriteLine(strMyString.PadLeft(30))
        Console.WriteLine(strMyString.PadLeft(20, "."c))
        
   End Sub
End Class


String.Replace

  
Imports System
Public Class MainClass
    Shared Sub Main()
        "Declare variables
        Dim strData As String
        Dim strNewData As String
        "Get the text from the TextBox
        strData = "Hello You"
        "Replace the string occurance
        strNewData = strData.Replace("Hello", "Goodbye")
        "Display the new string
        System.Console.WriteLine(strNewData)
    End Sub
End Class


String.Split

  
Public Class Tester
    Public Shared Sub Main
        Dim quote As String = "The important thing is not to " & _
            "stop questioning. --Albert Einstein"
        Dim strArray1() As String = Split(quote, "ing")
        Dim strArray2() As String = quote.Split(CChar("ing"))
        Dim counter As Integer
        For counter = 0 To strArray1.Length - 1
            Console.WriteLine(strArray1(counter))
        Next counter

        For counter = 0 To strArray2.Length - 1
            Console.WriteLine(strArray2(counter))
        Next counter
        
    End Sub

End Class


String.StartsWith

  
Imports System
Public Class MainClass
   Shared Sub Main()
      Dim strings As String()
      Dim i As Integer
      Dim quotes As Char = ChrW(34)
      strings = New String() {"started", "starting", _
         "ended", "ending"}
      Console.WriteLine(" test every string to see if it starts with "st"")
      For i = 0 To strings.GetUpperBound(0)
         If strings(i).StartsWith("st") Then
            Console.WriteLine(quotes & strings(i) & quotes & _
               " starts with " & quotes & "st" & quotes )
         End If
      Next
      Console.WriteLine(" test every string to see if it ends with "ed"")
      For i = 0 To strings.GetUpperBound(0)
         If strings(i).EndsWith("ed") Then
            Console.WriteLine( quotes & strings(i) & quotes & _
               " ends with " & quotes & "ed" & quotes )
         End If
      Next
   End Sub " Main
End Class


String.Substring(Int begin)

  

Public Class MainClass
   Public Shared Sub Main()
       "Strings
        Dim strConstant As String = "ABC"
        Dim strRepeat As New String("A"c, 20)
        Dim strMyString As String = "Hello World"
        Console.WriteLine(strMyString.Substring(0, 5))
        Console.WriteLine(strMyString.Substring(6))
        
   End Sub
End Class


String.Substring(Int begin, Int end)

  

Public Class MainClass
   Public Shared Sub Main()
       "Strings
        Dim strConstant As String = "ABC"
        Dim strRepeat As New String("A"c, 20)
        Dim strMyString As String = "Hello World"
        Console.WriteLine(strMyString.Substring(0, 5))
        Console.WriteLine(strMyString.Substring(6))
        
   End Sub
End Class


String.ToCharArray()

  


Imports System
Public Class MainClass
   Shared Sub Main()
      Dim string1 As String = "hello"
      Dim string2 As String = "GOOD BYE "
      Dim string3 As String = "   spaces   "
      Dim i As Integer
      Dim charArray() As Char = string1.ToCharArray()
      Console.WriteLine("string1 = " & string1 & vbCrLf & "string2 = " & _
         string2 & vbCrLf & "string3 = " & string3)
      For i = 0 To charArray.Length - 1
         Console.WriteLine(charArray(i))
      Next

   End Sub " Main
End Class


String.ToLower()

  
Public Class Tester
    Public Shared Sub Main
        Dim quote As String = "AbCdEfG"
        Dim result As New System.Text.StringBuilder
        result.AppendLine("Original:   " & quote)
        result.AppendLine("Upper Case: " & quote.ToUpper())
        result.AppendLine("Lower Case: " & quote.ToLower())
        result.AppendLine("Mixed Case: " & MixedCase(quote))
        Console.WriteLine(result.ToString())
    End Sub
    Public Shared Function MixedCase(ByVal origText As String) As String
        Dim counter As Integer
        Dim textParts() As String = Split(origText, " ")
        For counter = 0 To textParts.Length - 1
            If (textParts(counter).Length > 0) Then _
               textParts(counter) = _
               UCase(Microsoft.VisualBasic.Left( _
               textParts(counter), 1)) & _
               LCase(Mid(textParts(counter), 2))
        Next counter
        Return Join(textParts, " ")
    End Function
End Class


String.ToUpper()

  
Public Class Tester
    Public Shared Sub Main
        Dim quote As String = "AbCdEfG"
        Dim result As New System.Text.StringBuilder
        result.AppendLine("Original:   " & quote)
        result.AppendLine("Upper Case: " & quote.ToUpper())
        result.AppendLine("Lower Case: " & quote.ToLower())
        result.AppendLine("Mixed Case: " & MixedCase(quote))
        Console.WriteLine(result.ToString())
    End Sub
    Public Shared Function MixedCase(ByVal origText As String) As String
        Dim counter As Integer
        Dim textParts() As String = Split(origText, " ")
        For counter = 0 To textParts.Length - 1
            If (textParts(counter).Length > 0) Then _
               textParts(counter) = _
               UCase(Microsoft.VisualBasic.Left( _
               textParts(counter), 1)) & _
               LCase(Mid(textParts(counter), 2))
        Next counter
        Return Join(textParts, " ")
    End Function
End Class