VB.NET 窗体中插入子窗体

Imports System.Runtime.InteropServices

Public Class Form1

' 导入 SetParent 函数
<DllImport("user32.dll", SetLastError:=True)>
Private Shared Function SetParent(ByVal hWndChild As IntPtr, ByVal hWndNewParent As IntPtr) As IntPtr
End Function

' 导入 MoveWindow 函数
<DllImport("user32.dll", SetLastError:=True)>
Private Shared Function MoveWindow(ByVal hwnd As IntPtr, ByVal x As Integer, ByVal y As Integer, ByVal nWidth As Integer, ByVal nHeight As Integer, ByVal bRepaint As Boolean) As Boolean
End Function

' 导入 FindWindow 函数
<DllImport("user32.dll", SetLastError:=True)>
Private Shared Function FindWindow(ByVal lpClassName As String, ByVal lpWindowName As String) As IntPtr
End Function
' 申明常量
Private Const WM_PAINT As Integer = &HF

' 引入 SendMessage 函数
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr

' 查询窗口句柄
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    Dim handle As IntPtr = FindWindow("WeChatMainWndForPC", Nothing)

    If handle <> IntPtr.Zero Then
        ' 将句柄转换为十进制整数
        Dim handleDecimal As Integer = handle.ToInt32()
        ' 将句柄值显示在文本框中
        TextBox1.Text = handleDecimal.ToString()
    Else
        ' 如果未找到窗口则弹出消息框
        MessageBox.Show("未找到名为 ChatWnd 的窗口")
    End If
End Sub

' 创建子窗口并将其嵌入到指定窗口中
' 声明一个私有的方法，按钮 Button1 的单击事件处理程序。
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    ' 获取父窗口句柄：从 TextBox1 控件中读取文本内容，并将其转换为整数类型后创建一个 IntPtr 类型的句柄变量。
    Dim parentHWND As IntPtr = New IntPtr(CInt(TextBox1.Text))

    ' 创建子窗口：声明一个名为 subForm 的新的 Form 实例。
    Dim subForm As New Form()

    ' 设置子窗口标题为“子窗口”。
    subForm.Text = "子窗口"

    ' 设置子窗口的边框样式为固定对话框。
    subForm.FormBorderStyle = FormBorderStyle.FixedDialog

    ' 设置子窗口的启动位置为手动。
    subForm.StartPosition = FormStartPosition.Manual

    ' 设置子窗口的大小为 400x300 像素。
    subForm.Size = New Size(400, 300)

    ' 将子窗口的父句柄设置为父窗口句柄。
    SetParent(subForm.Handle, parentHWND)

    ' 重绘句柄内的组件并显示在子窗口上。
    SendMessage(parentHWND, WM_PAINT, IntPtr.Zero, IntPtr.Zero)

    ' 设置子窗口的位置和大小：通过 MoveWindow API 函数将子窗口移动到窗口的左上角，大小与子窗口相同。
    subForm.Show()
    MoveWindow(subForm.Handle, 0, 0, subForm.Width, subForm.Height, True)
End Sub

End Class