我的后台工作者在做他的工作时,我想更改主要形式的标签,以告知当时正在执行的流程。
该应用程序可以处理某些文件,因此我需要传递该应用程序正在处理的文件的信息。
我的后台工作者
Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
If (Not System.IO.Directory.Exists(caminho & "\results")) Then
System.IO.Directory.CreateDirectory(caminho & "\results")
End If
For Each folder As String In System.IO.Directory.GetDirectories(caminho)
Dim split As String() = folder.Split("\")
Dim parentFolder As String = split(split.Length - 1)
If (Not System.IO.Directory.Exists(caminho & "\results" & "\" & parentFolder)) Then
System.IO.Directory.CreateDirectory(caminho & "\results" & "\" & parentFolder)
End If
For Each file As String In System.IO.Directory.GetFiles(folder)
output = file
'Dim imgFile As System.Drawing.Image = System.Drawing.Image.FromFile(file)
Dim thumbimage As Bitmap
Dim originalimage As Bitmap
Dim width As Integer = TextBox2.Text '# this is the max width of the new image
Dim height As Integer = TextBox3.Text '# this is the max height of the new image
originalimage = System.Drawing.Image.FromFile(file)
thumbimage = New Bitmap(width, height)
Dim novonome As String = Path.GetFileNameWithoutExtension(file)
Dim gr As Graphics = Graphics.FromImage(thumbimage)
gr.DrawImage(originalimage, 0, 0, width, height)
thumbimage.Save(caminho & "\results" & "\" & parentFolder & "\" & novonome & ".png", Imaging.ImageFormat.Png)
thumbimage.Dispose()
originalimage.Dispose()
Next
Next
End Sub
我的进度更改:
Private Sub BackgroundWorker1_ProgressChanged(sender As Object, e As ProgressChangedEventArgs) Handles BackgroundWorker1.ProgressChanged
Label3.Text = "Working file " & output
End Sub
是否不应该使用正在工作的文件来更改form1中的label3.text?基本上,label3没有任何反应。
我的输出var在Public Class Form1下声明。
谢谢。
答案 0 :(得分:5)
确保您的BackgroundWorker对象具有WorkerReportsProgress = True
您必须从循环中调用进度:
For Each file As String In System.IO.Directory.GetFiles(folder)
BackgroundWorker1.ReportProgress(0, file)
...
然后在您的Progress事件中,读取状态:
Private Sub BackgroundWorker1_ProgressChanged(sender As Object, e As ProgressChangedEventArgs) Handles BackgroundWorker1.ProgressChanged
If e.UserState IsNot Nothing Then
Label3.Text = "Working file " & e.UserState.ToString
End If
End Sub