Question

我只是想弄清楚如何使用Background任务或者其他东西来将一些参数传递给后台任务，然后在完成任务时从任务中获取返回值并更新文本字段... < / p>

这就是我想在VB.NET中高级做的事情：

用户点击表格上的按钮
在后台线程中使用一些args执行HTTP请求
收到来自请求的回复后，请使用此数据更新表单

以下是代码：

    Public Class Form1
    Dim WebUpdateWorker As BackgroundWorker

    Private Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
        Dim arg1 As String = "Hi"
        Dim arg2 As Integer = 1
        WebUpdateWorker = New BackgroundWorker
        AddHandler WebUpdateWorker.DoWork, AddressOf DoWork
        AddHandler WebUpdateWorker.RunWorkerCompleted, AddressOf WorkFinished
        WebUpdateWorker.RunWorkerAsync()

    End Sub

    Public Function httpTask(ByVal arg1 As String, ByVal arg2 As Integer)
        ' do http request, return the http response
        Return "http response"
    End Function

    Private Sub DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs)
        ' I want to pass these values in instead of hard coding them here
        httpTask("Hi", 1)
    End Sub

    Private Sub WorkFinished(ByVal sender As Object, ByVal e As RunWorkerCompletedEventArgs)
        ' I want to use the returned value from httpTask here
        TextBox.Text = ("Result from background job: ")
    End Sub

End Class

VB.NET后台任务传递参数并在textfields中使用返回值

0 个答案: