VB.Net by API/System/String — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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(нет различий)
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Версия 19:40, 26 мая 2010
Содержание
- 1 String.Compare
- 2 String.Concat
- 3 String.Copy
- 4 String.Empty
- 5 String.Equals
- 6 String.Format
- 7 String.GetEnumerator
- 8 String.GetHashCode()
- 9 String.IndexOfAny(String sub)
- 10 String.IndexOfAny(String sub, Int count)
- 11 String.IndexOf(String substring)
- 12 String.Insert
- 13 String.IsNullOrEmpty
- 14 String.LastIndexOf
- 15 String.PadLeft(Int length)
- 16 String.PadLeft(Int length, String char)
- 17 String.Replace
- 18 String.Split
- 19 String.StartsWith
- 20 String.Substring(Int begin)
- 21 String.Substring(Int begin, Int end)
- 22 String.ToCharArray()
- 23 String.ToLower()
- 24 String.ToUpper()
String.Compare
<source lang="vbnet"> 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
</source>
String.Concat
<source lang="vbnet"> 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
</source>
String.Copy
<source lang="vbnet"> 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
</source>
String.Empty
<source lang="vbnet">
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
</source>
String.Equals
<source lang="vbnet"> 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
</source>
String.Format
<source lang="vbnet">
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
</source>
String.GetEnumerator
<source lang="vbnet">
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
</source>
String.GetHashCode()
<source lang="vbnet">
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
</source>
String.IndexOfAny(String sub)
<source lang="vbnet"> 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
</source>
String.IndexOfAny(String sub, Int count)
<source lang="vbnet"> 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
</source>
String.IndexOf(String substring)
<source lang="vbnet"> 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
</source>
String.Insert
<source lang="vbnet"> 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
</source>
String.IsNullOrEmpty
<source lang="vbnet"> 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
</source>
String.LastIndexOf
<source lang="vbnet"> 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
</source>
String.PadLeft(Int length)
<source lang="vbnet">
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
</source>
String.PadLeft(Int length, String char)
<source lang="vbnet"> 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
</source>
String.Replace
<source lang="vbnet"> 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
</source>
String.Split
<source lang="vbnet"> 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
</source>
String.StartsWith
<source lang="vbnet"> 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
</source>
String.Substring(Int begin)
<source lang="vbnet">
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
</source>
String.Substring(Int begin, Int end)
<source lang="vbnet">
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
</source>
String.ToCharArray()
<source lang="vbnet">
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
</source>
String.ToLower()
<source lang="vbnet"> 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
</source>
String.ToUpper()
<source lang="vbnet"> 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
</source>