控制一个表单多次打开

Question

假设我多次打开同一个表单，但我只想控制其中一个（一个 fe 具有“hello”作为窗口标题（文本） <- 来识别）

我该如何做到这一点？

编辑：这是我想做的一个例子（它有点复杂，我不擅长解释我想要什么）

private void openthesecformfirst_Click(object sender, EventArgs e)

{

    Form2 sec = new Form2();

    sec.Text = "Hi";

    sec.Show();

    //The second form is now opened

}

private void openthesecformsecond_Click(object sender, EventArgs e)

{

    Form2 sec = new Form2();

    sec.Text = "Hello";

    sec.Show();

    //the second form is now opened twice

}

private void changelabelinfirst_Click(object sender, EventArgs e)

{

    //Identified by the title the first opened form2 is supposed to change a label text

    //How do I get this one specifically?

}

private void changelabelinsecond_Click(object sender, EventArgs e)

{

    //Identified by the title the second opened form2 is supposed to change a label text

    //How do I get this one specifically?

}

Answer 1

对于 OS Windows 中的查找窗口，您可以使用FindWindowExWin32 Api，例如：因为这是原始的不安全代码，您应该从 user32.dll 导入函数：[DllImport("user32.dll", SetLastError = true)] static extern IntPtr&nbsp;FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter,&nbsp;string lpszClass, string lpszWindow);[DllImport("user32.dll", SetLastError = true)]public static extern IntPtr FindWindowEx(IntPtr parentHandle, IntPtr&nbsp;childAfter,&nbsp;string className,&nbsp; string windowTitle);导入后，您可以使用这样的功能：&nbsp;var CaptionTextForLooking = "hello"; // or "Hi"&nbsp;var foundWindowPtr =&nbsp;&nbsp;FindWindowEx(IntPtr.Zero,IntPtr.Zero,CaptionTextForLooking&nbsp;&nbsp;,IntPtr.Zero);

Answer 2

您可以使用Application.OpenForms属性。