Question

新手问题，但我似乎无法找到明确的方法来做到这一点。我希望程序能够从特定的文本文件行中获取信息，并将该信息用于各种任务。如果您还可以教我如何写入文本文件的特定行，我真的很感激。

以下是文本文件的示例：

Line1 Name = Garry

Line2 Set = 0

Line3其他=其他

还有更多行

棘手的部分是抓住第2行'='之后的信息。而且，如果用户想要更改这些行中的一个信息，我将如何改变它......我将非常感谢任何帮助。

*在.net 4.5上使用Visual Basic Studio 2012

Answer 1

如果你想这么做：

首先阅读文件的所有行

Dim Lines() as String = IO.File.ReadAllLines("C:\myfile.txt")

然后，数组包含文件中每行的元素。

然后迭代这些行：

Dim MyKeyValues As New Dictionary(Of String, String) 'See below
For each line as String in Lines
  Dim LineParts() as String = Strings.Split(line, "=", 2) 'Split the current line into two chunks at the first =
  If LineParts.Count < 2 Then
    Continue For 'No = in the line, so skip it
  Else
    Dim Key as String = LineParts(0)
    Dim Value as String = LineParts(1) 'This contains the part after the =
    'Do whatever you want with the value here. e.g.
    MyKeyValues.Add(Key, Value) 'See below
  Endif
Next

您可以将行部分保存到Dictionary(Of String, String)并对此词典中的值进行更改。然后将字典写回文件：

Dim FileLines as New List(Of String)
For each k as String in MyKeyValues.Keys
  FileLines.Add(k & "=" & MyKeyValues(k))
Next
IO.File.WriteAllLines("C:\myfile.txt", FileLines)

如果文本文件不是非常大，则ReadAllLines（）和WriteAllLines（）方法应该相当快。正如其他人指出的那样，INIFile类应该最适合您的需求，因为这样可以轻松读取和更改密钥。

Answer 2

这与INI文件非常相似，只是没有标题。

以下是INI文件的示例：

[CONFIG]                Header
Option1=true            Key=Value
Option2=true            Key=Value
Option3=false           Key=Value

您可以在项目中使用此类轻松读取和写入INI文件：

Imports System.IO
Imports System.Text.RegularExpressions
Imports System.Collections
Imports System.Diagnostics

Public Class IniFile
' List of IniSection objects keeps track of all the sections in the INI file
Private m_sections As Hashtable

' Public constructor
Public Sub New()
    m_sections = New Hashtable(StringComparer.InvariantCultureIgnoreCase)
End Sub

' Loads the Reads the data in the ini file into the IniFile object
Public Sub Load(ByVal sFileName As String, Optional ByVal bMerge As Boolean = False)
    If Not bMerge Then
        RemoveAllSections()
    End If
    '  Clear the object... 
    Dim tempsection As IniSection = Nothing
    Dim oReader As New StreamReader(sFileName)
    Dim regexcomment As New Regex("^([\s]*#.*)", (RegexOptions.Singleline Or RegexOptions.IgnoreCase))
    ' Broken but left for history
    'Dim regexsection As New Regex("\[[\s]*([^\[\s].*[^\s\]])[\s]*\]", (RegexOptions.Singleline Or RegexOptions.IgnoreCase))
    Dim regexsection As New Regex("^[\s]*\[[\s]*([^\[\s].*[^\s\]])[\s]*\][\s]*$", (RegexOptions.Singleline Or RegexOptions.IgnoreCase))
    Dim regexkey As New Regex("^\s*([^=\s]*)[^=]*=(.*)", (RegexOptions.Singleline Or RegexOptions.IgnoreCase))
    While Not oReader.EndOfStream
        Dim line As String = oReader.ReadLine()
        If line <> String.Empty Then
            Dim m As Match = Nothing
            If regexcomment.Match(line).Success Then
                m = regexcomment.Match(line)
                Trace.WriteLine(String.Format("Skipping Comment: {0}", m.Groups(0).Value))
            ElseIf regexsection.Match(line).Success Then
                m = regexsection.Match(line)
                Trace.WriteLine(String.Format("Adding section [{0}]", m.Groups(1).Value))
                tempsection = AddSection(m.Groups(1).Value)
            ElseIf regexkey.Match(line).Success AndAlso tempsection IsNot Nothing Then
                m = regexkey.Match(line)
                Trace.WriteLine(String.Format("Adding Key [{0}]=[{1}]", m.Groups(1).Value, m.Groups(2).Value))
                tempsection.AddKey(m.Groups(1).Value).Value = m.Groups(2).Value
            ElseIf tempsection IsNot Nothing Then
                '  Handle Key without value
                Trace.WriteLine(String.Format("Adding Key [{0}]", line))
                tempsection.AddKey(line)
            Else
                '  This should not occur unless the tempsection is not created yet...
                Trace.WriteLine(String.Format("Skipping unknown type of data: {0}", line))
            End If
        End If
    End While
    oReader.Close()
End Sub

' Used to save the data back to the file or your choice
Public Sub Save(ByVal sFileName As String)
    Dim oWriter As New StreamWriter(sFileName, False)
    For Each s As IniSection In Sections
        Trace.WriteLine(String.Format("Writing Section: [{0}]", s.Name))
        oWriter.WriteLine(String.Format("[{0}]", s.Name))
        For Each k As IniSection.IniKey In s.Keys
            If k.Value <> String.Empty Then
                Trace.WriteLine(String.Format("Writing Key: {0}={1}", k.Name, k.Value))
                oWriter.WriteLine(String.Format("{0}={1}", k.Name, k.Value))
            Else
                Trace.WriteLine(String.Format("Writing Key: {0}", k.Name))
                oWriter.WriteLine(String.Format("{0}", k.Name))
            End If
        Next
    Next
    oWriter.Close()
End Sub

' Gets all the sections
Public ReadOnly Property Sections() As System.Collections.ICollection
    Get
        Return m_sections.Values
    End Get
End Property

' Adds a section to the IniFile object, returns a IniSection object to the new or existing object
Public Function AddSection(ByVal sSection As String) As IniSection
    Dim s As IniSection = Nothing
    sSection = sSection.Trim()
    ' Trim spaces
    If m_sections.ContainsKey(sSection) Then
        s = DirectCast(m_sections(sSection), IniSection)
    Else
        s = New IniSection(Me, sSection)
        m_sections(sSection) = s
    End If
    Return s
End Function

' Removes a section by its name sSection, returns trus on success
Public Function RemoveSection(ByVal sSection As String) As Boolean
    sSection = sSection.Trim()
    Return RemoveSection(GetSection(sSection))
End Function

' Removes section by object, returns trus on success
Public Function RemoveSection(ByVal Section As IniSection) As Boolean
    If Section IsNot Nothing Then
        Try
            m_sections.Remove(Section.Name)
            Return True
        Catch ex As Exception
            Trace.WriteLine(ex.Message)
        End Try
    End If
    Return False
End Function

'  Removes all existing sections, returns trus on success
Public Function RemoveAllSections() As Boolean
    m_sections.Clear()
    Return (m_sections.Count = 0)
End Function

' Returns an IniSection to the section by name, NULL if it was not found
Public Function GetSection(ByVal sSection As String) As IniSection
    sSection = sSection.Trim()
    ' Trim spaces
    If m_sections.ContainsKey(sSection) Then
        Return DirectCast(m_sections(sSection), IniSection)
    End If
    Return Nothing
End Function

'  Returns a KeyValue in a certain section
Public Function GetKeyValue(ByVal sSection As String, ByVal sKey As String) As String
    Dim s As IniSection = GetSection(sSection)
    If s IsNot Nothing Then
        Dim k As IniSection.IniKey = s.GetKey(sKey)
        If k IsNot Nothing Then
            Return k.Value
        End If
    End If
    Return String.Empty
End Function

' Sets a KeyValuePair in a certain section
Public Function SetKeyValue(ByVal sSection As String, ByVal sKey As String, ByVal sValue As String) As Boolean
    Dim s As IniSection = AddSection(sSection)
    If s IsNot Nothing Then
        Dim k As IniSection.IniKey = s.AddKey(sKey)
        If k IsNot Nothing Then
            k.Value = sValue
            Return True
        End If
    End If
    Return False
End Function

' Renames an existing section returns true on success, false if the section didn't exist or there was another section with the same sNewSection
Public Function RenameSection(ByVal sSection As String, ByVal sNewSection As String) As Boolean
    '  Note string trims are done in lower calls.
    Dim bRval As Boolean = False
    Dim s As IniSection = GetSection(sSection)
    If s IsNot Nothing Then
        bRval = s.SetName(sNewSection)
    End If
    Return bRval
End Function

' Renames an existing key returns true on success, false if the key didn't exist or there was another section with the same sNewKey
Public Function RenameKey(ByVal sSection As String, ByVal sKey As String, ByVal sNewKey As String) As Boolean
    '  Note string trims are done in lower calls.
    Dim s As IniSection = GetSection(sSection)
    If s IsNot Nothing Then
        Dim k As IniSection.IniKey = s.GetKey(sKey)
        If k IsNot Nothing Then
            Return k.SetName(sNewKey)
        End If
    End If
    Return False
End Function

' Remove a key by section name and key name
Public Function RemoveKey(ByVal sSection As String, ByVal sKey As String) As Boolean
    Dim s As IniSection = GetSection(sSection)
    If s IsNot Nothing Then
        Return s.RemoveKey(sKey)
    End If
    Return False
End Function

' IniSection class 
Public Class IniSection
    '  IniFile IniFile object instance
    Private m_pIniFile As IniFile
    '  Name of the section
    Private m_sSection As String
    '  List of IniKeys in the section
    Private m_keys As Hashtable

    ' Constuctor so objects are internally managed
    Protected Friend Sub New(ByVal parent As IniFile, ByVal sSection As String)
        m_pIniFile = parent
        m_sSection = sSection
        m_keys = New Hashtable(StringComparer.InvariantCultureIgnoreCase)
    End Sub

    ' Returns all the keys in a section
    Public ReadOnly Property Keys() As System.Collections.ICollection
        Get
            Return m_keys.Values
        End Get
    End Property

    ' Returns the section name
    Public ReadOnly Property Name() As String
        Get
            Return m_sSection
        End Get
    End Property

    ' Adds a key to the IniSection object, returns a IniKey object to the new or existing object
    Public Function AddKey(ByVal sKey As String) As IniKey
        sKey = sKey.Trim()
        Dim k As IniSection.IniKey = Nothing
        If sKey.Length <> 0 Then
            If m_keys.ContainsKey(sKey) Then
                k = DirectCast(m_keys(sKey), IniKey)
            Else
                k = New IniSection.IniKey(Me, sKey)
                m_keys(sKey) = k
            End If
        End If
        Return k
    End Function

    ' Removes a single key by string
    Public Function RemoveKey(ByVal sKey As String) As Boolean
        Return RemoveKey(GetKey(sKey))
    End Function

    ' Removes a single key by IniKey object
    Public Function RemoveKey(ByVal Key As IniKey) As Boolean
        If Key IsNot Nothing Then
            Try
                m_keys.Remove(Key.Name)
                Return True
            Catch ex As Exception
                Trace.WriteLine(ex.Message)
            End Try
        End If
        Return False
    End Function

    ' Removes all the keys in the section
    Public Function RemoveAllKeys() As Boolean
        m_keys.Clear()
        Return (m_keys.Count = 0)
    End Function

    ' Returns a IniKey object to the key by name, NULL if it was not found
    Public Function GetKey(ByVal sKey As String) As IniKey
        sKey = sKey.Trim()
        If m_keys.ContainsKey(sKey) Then
            Return DirectCast(m_keys(sKey), IniKey)
        End If
        Return Nothing
    End Function

    ' Sets the section name, returns true on success, fails if the section
    ' name sSection already exists
    Public Function SetName(ByVal sSection As String) As Boolean
        sSection = sSection.Trim()
        If sSection.Length <> 0 Then
            ' Get existing section if it even exists...
            Dim s As IniSection = m_pIniFile.GetSection(sSection)
            If s IsNot Me AndAlso s IsNot Nothing Then
                Return False
            End If
            Try
                ' Remove the current section
                m_pIniFile.m_sections.Remove(m_sSection)
                ' Set the new section name to this object
                m_pIniFile.m_sections(sSection) = Me
                ' Set the new section name
                m_sSection = sSection
                Return True
            Catch ex As Exception
                Trace.WriteLine(ex.Message)
            End Try
        End If
        Return False
    End Function

    ' Returns the section name
    Public Function GetName() As String
        Return m_sSection
    End Function

    ' IniKey class
    Public Class IniKey
        '  Name of the Key
        Private m_sKey As String
        '  Value associated
        Private m_sValue As String
        '  Pointer to the parent CIniSection
        Private m_section As IniSection

        ' Constuctor so objects are internally managed
        Protected Friend Sub New(ByVal parent As IniSection, ByVal sKey As String)
            m_section = parent
            m_sKey = sKey
        End Sub

        ' Returns the name of the Key
        Public ReadOnly Property Name() As String
            Get
                Return m_sKey
            End Get
        End Property

        ' Sets or Gets the value of the key
        Public Property Value() As String
            Get
                Return m_sValue
            End Get
            Set(ByVal value As String)
                m_sValue = value
            End Set
        End Property

        ' Sets the value of the key
        Public Sub SetValue(ByVal sValue As String)
            m_sValue = sValue
        End Sub
        ' Returns the value of the Key
        Public Function GetValue() As String
            Return m_sValue
        End Function

        ' Sets the key name
        ' Returns true on success, fails if the section name sKey already exists
        Public Function SetName(ByVal sKey As String) As Boolean
            sKey = sKey.Trim()
            If sKey.Length <> 0 Then
                Dim k As IniKey = m_section.GetKey(sKey)
                If k IsNot Me AndAlso k IsNot Nothing Then
                    Return False
                End If
                Try
                    ' Remove the current key
                    m_section.m_keys.Remove(m_sKey)
                    ' Set the new key name to this object
                    m_section.m_keys(sKey) = Me
                    ' Set the new key name
                    m_sKey = sKey
                    Return True
                Catch ex As Exception
                    Trace.WriteLine(ex.Message)
                End Try
            End If
            Return False
        End Function

        ' Returns the name of the Key
        Public Function GetName() As String
            Return m_sKey
        End Function
    End Class
    ' End of IniKey class
End Class
' End of IniSection class
End Class

以下是如何使用此类的示例：

Private Sub WriteValuesToIniFile()
    Dim IniFileConfig As New IniFile
    IniFileConfig.Load("C:\User\SumGuy\Desktop\Config.ini")
    IniFileConfig.SetKeyValue("CONFIG", "Key1", "Value")
    IniFileConfig.Save("C:\User\SumGuy\Desktop\Config.ini")
End Sub

这会将此内容写入ini文件：

[CONFIG]
Key1=Value

逐行读取文本文件并从进行中获取输入'='

2 个答案: