LINQ 中的分区运算符
将输入序列划分为两个独立的部分，不重新排列序列的元素，然后返回其中一个部分。
| 运算符 | 描述 | C# 查询表达式语法 | VB 查询表达式语法 |
|---|---|---|---|
| Skip | 跳过序列中指定的某些数量的元素，并返回剩下的元素 | 不可用 | Skip |
| SkipWhile | 如 Skip 相同，唯一的例外是跳过的元素数量由布尔条件指定 | 不可用 | Skip While |
| Take | 从序列中获取指定数量的元素，并跳过剩下的元素 | 不可用 | Take |
| TakeWhile | 如 Take 相同，但所取元素数量由布尔条件指定 | 不可用 | Take While |
Skip 的示例 - 查询表达式
VB
Module Module1
Sub Main()
Dim words = {"once", "upon", "a", "time", "there", "was", "a", "jungle"}
Dim query = From word In words
Skip 4
Dim sb As New System.Text.StringBuilder()
For Each str As String In query
sb.AppendLine(str)
Console.WriteLine(str)
Next
Console.ReadLine()
End Sub
End Module
编译并执行 VB 中的上述代码后，它生成以下结果 -
there was a jungle
Skip While 的示例 - 查询表达式
VB
Module Module1
Sub Main()
Dim words = {"once", "upon", "a", "time", "there", "was", "a", "jungle"}
Dim query = From word In words
Skip While word.Substring(0, 1) = "t"
Dim sb As New System.Text.StringBuilder()
For Each str As String In query
sb.AppendLine(str)
Console.WriteLine(str)
Next
Console.ReadLine()
End Sub
End Module
编译并执行 VB 中的上述代码后，它生成以下结果 -
once upon a was a jungle
Take 的示例 - 查询表达式
VB
Module Module1
Sub Main()
Dim words = {"once", "upon", "a", "time", "there", "was", "a", "jungle"}
Dim query = From word In words
Take 3
Dim sb As New System.Text.StringBuilder()
For Each str As String In query
sb.AppendLine(str)
Console.WriteLine(str)
Next
Console.ReadLine()
End Sub
End Module
编译并执行 VB 中的上述代码后，它生成以下结果 -
once upon a
Take While 的示例 - 查询表达式
VB
Module Module1
Sub Main()
Dim words = {"once", "upon", "a", "time", "there", "was", "a", "jungle"}
Dim query = From word In words
Take While word.Length < 6
Dim sb As New System.Text.StringBuilder()
For Each str As String In query
sb.AppendLine(str)
Console.WriteLine(str)
Next
Console.ReadLine()
End Sub
End Module
编译并执行 VB 中的上述代码后，它生成以下结果 -
once upon a time there was a
linq_query_operators.htm
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