67 lines
1.8 KiB
VB.net
67 lines
1.8 KiB
VB.net
Module Module1
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Sub Main()
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'string creation
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Dim x = "hello world"
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' mark string for garbage collection
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x = Nothing
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' string assignment with a null byte
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x = "ab" + Chr(0)
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Console.WriteLine(x)
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Console.WriteLine(x.Length)
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'string comparison
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If x = "hello" Then
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Console.WriteLine("equal")
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Else
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Console.WriteLine("not equal")
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End If
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If x.CompareTo("bc") = -1 Then
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Console.WriteLine("x is lexicographically less than 'bc'")
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End If
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'string cloning
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Dim c(3) As Char
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x.CopyTo(0, c, 0, 3)
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Dim objecty As New String(c)
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Dim y As New String(c)
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Console.WriteLine(x = y) 'same as string.equals
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Console.WriteLine(x.Equals(y)) 'it overrides object.equals
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Console.WriteLine(x = objecty) 'uses object.equals, return false
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'check if empty
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Dim empty = ""
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Dim nullString As String = Nothing
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Dim whitespace = " "
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If IsNothing(nullString) AndAlso empty = String.Empty _
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AndAlso String.IsNullOrEmpty(nullString) AndAlso String.IsNullOrEmpty(empty) _
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AndAlso String.IsNullOrWhiteSpace(nullString) AndAlso String.IsNullOrWhiteSpace(empty) _
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AndAlso String.IsNullOrWhiteSpace(whitespace) Then
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Console.WriteLine("Strings are null, empty or whitespace")
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End If
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'append a byte
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x = "helloworld"
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x += Chr(83)
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Console.WriteLine(x)
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'substring
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Dim slice = x.Substring(5, 5)
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Console.WriteLine(slice)
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'replace bytes
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Dim greeting = x.Replace("worldS", "")
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Console.WriteLine(greeting)
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'join strings
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Dim join = greeting + " " + slice
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Console.WriteLine(join)
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End Sub
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End Module
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