从另一个进程更新TextBox文本 [英] Updating TextBox text from another process

问题描述

我有两个WinForms应用程序，我需要从Application2向Application1中的TextBox添加文本.我已经使用命名管道和WCF成功完成了此操作.我可以成功地从Application2调用Application1中的方法，但是我收到" Invoke或BeginInvoke不能在控件上调用，直到创建了窗口句柄."错误或文本框未更新为全部.

I have two WinForms applications and I need to add text to TextBox in Application1 from Application2. I've successfully done this using named pipes and WCF. I can successfuly call a method in Application1 from Application2 but I'm getting either "Invoke or BeginInvoke cannot be called on a control until the window handle has been created." error or the textbox is not updated at all.

这是我的基本代码. GetMessage 由Application2调用.这个根本不会更新TextBox:

Here's my basic code. GetMessage is called by Application2. This one doesn't update TextBox at all:

public void GetMessage(string msg)
{
    UpdateTextbox(msg);
}

private void UpdateTextbox(string msg)
{
    this.textBox1.Text += msg + Environment.NewLine;
}

这引发了Invoke错误:

This one throws Invoke error:

public void GetMessage(string msg)
{
    Action a = () => UpdateTextbox(msg);
    textBox1.BeginInvoke(a);
}

我试图通过强制创建句柄来欺骗自己的方式，但是它也不会更新TextBox:

I tried to cheat my way by forcing creation of the handle with this, but it doesn't update TextBox either:

public void GetMessage(string msg)
{
    IntPtr handle = textBox1.Handle;
    Action a = () => UpdateTextbox(msg);
    textBox1.BeginInvoke(a);
}

我该怎么办?

推荐答案

由于问题在于Form1的文本框位于Form1的另一个实例上.从 Application1.Form1 中观察以下代码，该代码将启动命名管道服务:

The problem is that the TextBox of the Form1 was on another instance of the Form1. Observe this code from Application1.Form1 which starts the named pipe service:

private void Form1_Load(object sender, EventArgs e)
{
    ServiceHost host = new ServiceHost(typeof(Form1), new Uri[] { new Uri("net.pipe://localhost") });
    host.AddServiceEndpoint(typeof(ISmsService), new NetNamedPipeBinding(), "PipeReverse");
    host.Open();
}

如果我理解正确，这将启动 Form1 的实例.因此，当Application2调用 Application1.GetMessage 时，它将调用 ServiceHost-instance-Form1.GetMessage .

If I am understanding it right, this starts an instance of Form1. Thus, when Application2 calls Application1.GetMessage, it calls ServiceHost-instance-Form1.GetMessage.

要访问 Form1 的主实例，我将代码更改为:

To access main instance of Form1 I changed my code to this:

public Form1()
{
    InitializeComponent();

    if (mainForm == null)
    {
        mainForm = this;
    }
}

private static Form1 mainForm;
public static Form1 MainForm
{
    get
    {
        return mainForm;
    }
}

private void UpdateTextbox(string msg)
{
    MainForm.textBox1.Text += msg + Environment.NewLine;
}

现在可以正常工作了.

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