Question

我正在尝试制作一个程序，该程序读取一个选定的XML文件，另一个程序将其现在正在播放的歌曲和艺术家写入每首歌曲的开头。

这是我到目前为止所做的，但是我需要连续循环的代码，以便在自动加载新歌并编辑XML文件时，它也将在此更新。

Imports System
Imports System.Xml

Public Class MainForm

'Variables Declared'

'Saves file path as path'
Public XMLPath As String
'Full path to selected file'
Dim Path As String = Me.XMLPath

Private Sub LoadXMLButton_Click(sender As Object, e As EventArgs) Handles LoadXML_Button.Click

    'Filehandle to to open dialog
    Dim XMLPathFileHandle As OpenFileDialog = New OpenFileDialog

    'Title of dialog box
    XMLPathFileHandle.Title = "Select XML file"

    'File types which file dialog accepts
    XMLPathFileHandle.Filter = "All files (*.xml)|*.xml"

    'if user clicks ok
    If XMLPathFileHandle.ShowDialog() = Windows.Forms.DialogResult.OK Then

        'save selected file path
        XMLPath = XMLPathFileHandle.FileName

        'show file path in combobox
        ComboBox1.Text = XMLPath

    End If

End Sub

Private Sub StartButton_Click(sender As Object, e As EventArgs) Handles StartButton.Click

        'check if file exists
        If (IO.File.Exists(XMLPath)) Then

            'create a new xmltextreader object
            'this is the object that we will loop and will be used to read the xml file
            Dim document As XmlReader = New XmlTextReader(XMLPath)

            'loop through the xml file
            While (document.Read())

                Dim type = document.NodeType

                'if node type was element
                If (type = XmlNodeType.Element) Then

                    'if the loop found a <ARTIST> tag
                    If (document.Name = "ARTIST") Then

                        TextBox1.Text = document.ReadInnerXml.ToString()

                    End If

                    'if the loop found a <TITLE> tag
                    If (document.Name = "TITLE") Then

                        TextBox2.Text = document.ReadInnerXml.ToString()

                    End If

                End If

            End While

            'close XML to avoid error with saving
            document.Close()

        Else

            MessageBox.Show("The filename you selected was not found.")

        End If

End Sub

Answer 1

示例代码

- 首先添加FileSystemWatcher（来自工具箱）

   Imports System

导入System.Xml Imports System.IO

Public Class Form1

'Variables Declared'

Dim XMLPath, Path_filename, Path_url As String



Private Sub LoadXMLButton_Click(sender As Object, e As EventArgs) Handles LoadXML_Button.Click

    'Filehandle to to open dialog
    Dim XMLPathFileHandle As OpenFileDialog = New OpenFileDialog

    'Title of dialog box
    XMLPathFileHandle.Title = "Select XML file"

    'File types which file dialog accepts
    XMLPathFileHandle.Filter = "All files (*.xml)|*.xml"

    'if user clicks ok
    If XMLPathFileHandle.ShowDialog() = Windows.Forms.DialogResult.OK Then

        'save selected file path
        XMLPath = XMLPathFileHandle.FileName

        'show file path in combobox
        XMLdirectory.Text = XMLPath


        Dim filePath As String = XMLPathFileHandle.FileName
        Dim directoryPath As String = Path.GetDirectoryName(filePath)

        Path_url = directoryPath
        Path_filename = XMLPathFileHandle.SafeFileName


        ''********* ADD THIS AREA
        FileSystemWatcher1.Path = Path_url

        ''For file watch start
        FileSystemWatcher1.EnableRaisingEvents = True
        ''*******************************
    End If

End Sub



' Add a FileSystemWatcher object from toolbox

Private Sub FileSystemWatcher1_Changed(sender As Object, e As FileSystemEventArgs) Handles FileSystemWatcher1.Changed
    TextBox1.Text = " file changed "

    'processs()


End Sub

Private Sub processs()
    Dim document As XmlReader = New XmlTextReader(XMLPath)
    'check if file exists
    If (IO.File.Exists(XMLPath)) Then

        Dim type = document.NodeType

        'if node type was element
        If (type = XmlNodeType.Element) Then

            'if the loop found a <ARTIST> tag
            If (document.Name = "ARTIST") Then
                TextBox1.Text = document.ReadInnerXml.ToString()
            End If

            'if the loop found a <TITLE> tag
            If (document.Name = "TITLE") Then
                TextBox2.Text = document.ReadInnerXml.ToString()
            End If

        End If
        'close XML to avoid error with saving
        document.Close()
    End If
End Sub

结束班

我认为你想要吗？试试吧。如果您有问题，我会检查。

这是runnig代码

扫描XML时连续循环

1 个答案: