Question

我正在读记事本。当我在visual basic中使用sort函数对它们进行排序时，我注意到结果不准确。

For example 
hello i am who 1
I am who hello 14
am hello who I 13

我需要排序第五列，任何想法如何在visual basic中做到这一点？

Answer 1

您可以通过将文本文件中的数据解析为元组列表，然后使用orderby按第五列排序来实现此目的，例如：

Module Module1
    Sub Main()
        'I put this dialog here so you can browse to wherever your text file is
        Dim SelectFileDialog As New OpenFileDialog        
        Dim Result As DialogResult = SelectFileDialog.ShowDialog()

        If(Result <> DialogResult.OK)
            Exit Sub

        End If

        Dim FilePath As String = SelectFileDialog.FileName

        'read all the lines from the text file, store it in a string array
        Dim FileLines() As String = IO.File.ReadAllLines(FilePath)

        'make a temporary list of tuples,                   (5th column, full line)
        Dim UnsortedLinesByFifthColumn As New List(Of Tuple(Of String, String))

        For Each Line As String In FileLines

            'get the string on the fifth column of the line, it looks like your columns are delimited by spaces. 
            Dim FifthColumnString as String = Line.Split(" ")(4)

            'make a tuple representing each line, so we can sort it easily
            '                                             Item1              Item2
            Dim LineTuple As New Tuple(Of String, String)(FifthColumnString, Line)

            UnsortedLinesByFifthColumn.Add(LineTuple)
        Next

        'use OrderBy and a lambda expression to sort by the string in the fifth column
        Dim SortedLinesByFifthColumn As List(Of Tuple(Of String, String)) = UnsortedLinesByFifthColumn.OrderBy(Function(a) a.Item1).ToList()

        'print out the lines sorted by the fifth column
        For Each SortedLine As Tuple(Of String, String) In SortedLinesByFifthColumn
            Dim OriginalLine As String = SortedLine.Item2
            Console.WriteLine(OriginalLine)

        Next

        'stop the program so you can read what was printed to the console
        Stop

    End Sub

End Module

输入：

SomeTextFile.txt

hello i am who 1
I am who hello 14
am hello who I 13

输出（控制台）

hello i am who 1
am hello who I 13
I am who hello 14

请注意，我假设您要按第五个空格分隔列对行进行排序;如果这不是您要求的，请编辑您的问题，我会更新此答案。

在vb.net中对特定列进行排序

1 个答案: