C# 如何用获取文本框的句柄,并且获取文本框里面的值?
C# 如何用获取某个应用程序里面的文本框的句柄,并且获取文本框里面的值?
我是要拿到那个程序里面文本框的句柄.
IntPtr ab = new IntPtr();
StringBuilder className = new StringBuilder(256);
IntPtr ip = User32API.FindWindow("Notepad", "Raybelly.txt - 记事本");
IntPtr b = User32API.FindWindowEx(ip, ab, "Edit", null);
User32API.GetWindowText(b, className, className.Capacity);
MessageBox.Show(className.ToString());
我现在已经拿到文本框的句柄了,但是GetWindowText方法拿不出里面的值?
const int HWND_TOPMOST = -1;
const int SWP_SHOWWINDOW = 40;
const int WM_GETTEXT = 0x000D;
private void Form1_Load(object sender, System.EventArgs e)
{
IntPtr ab = new IntPtr();
StringBuilder className = new StringBuilder(256);
IntPtr ip = User32API.FindWindow("Notepad", "Raybelly.txt - 记事本");
IntPtr b = User32API.FindWindowEx(ip, ab, "Edit", null);
//User32API.GetWindowText(b, className, className.Capacity);
//MessageBox.Show(className.ToString());
string w = "";
IntPtr ptr = Marshal.StringToHGlobalAnsi(w);
if (User32API.SendMessage(b, WM_GETTEXT, 100000, ptr))
MessageBox.Show(Marshal.PtrToStringAnsi(ptr));
}
const int HWND_TOPMOST = -1;
const int SWP_SHOWWINDOW = 40;
const int WM_GETTEXT = 0x000D;
private void Form1_Load(object sender, System.EventArgs e)
{
IntPtr ab = new IntPtr();
StringBuilder className = new StringBuilder(256);
IntPtr ip = User32API.FindWindow("Notepad", "Raybelly.txt - 记事本");
IntPtr b = User32API.FindWindowEx(ip, ab, "Edit", null);
//User32API.GetWindowText(b, className, className.Capacity);
//MessageBox.Show(className.ToString());
string w = "";
IntPtr ptr = Marshal.StringToHGlobalAnsi(w);
if (User32API.SendMessage(b, WM_GETTEXT, 100000, ptr))
MessageBox.Show(Marshal.PtrToStringAnsi(ptr));
}
参照以上资材(网上下载的)编写了我自己的程序,运行过程中发现功能没有问题,但是经常死机,卡死。
应该反复寻找,找到了额问题点的所在
string w="" ; 申请的是空字符串,而 if (User32API.SendMessage(b, WM_GETTEXT, 100000, ptr)) 使用了100000个字符串。
运行一次两次没有问题,如果经常使用 会出现 卡死,死机的问题发生
解决办法 string w="" ; 变更为 string w=new string(new char[100000]);
这样就解决问题了
句柄太消耗CPU资源了
以下是我优化后直接使用StringBuilder 来接收数据
using System.Runtime.InteropServices;
[DllImport("user32.dll", EntryPoint = "SendMessage")]
private static extern void SendMessage(IntPtr hwnd, int wMsg, int wParam, StringBuilder lParam);
// rfptr为主菜单的句柄
rfptr = FindWindow(null, "要寻找的标题名称");
//child_2为文本框的 句柄
child_2 = FindWindowEx(rfptr, child_two, "要寻找的类名称");
StringBuilder strbu = new StringBuilder(102);
SendMessage(child_2, 0x0d, 100, strbu);
//label1.text输出找到的文档
label1.text=strbu.tostring();
面是转载自:http://www.cnblogs.com/me-sa/articles/669402.html
SendMessage是一个在user32.dll中声明的API函数,在C#中导入如下:
using System.Runtime.InteropServices;[DllImport("user32.dll", EntryPoint="SendMessageA")]public static extern int SendMessage (IntPtr hwnd, int wMsg, IntPtr wParam, IntPtr lParam);
本文描述其参数 lParam 的用法,主要是数据类型之间的转化。
● 一种最简单的处理方式是声明多个SendMessage函数(overload),用所需的数据类型直接替换IntPtr。例如:
//声明:[DllImport("user32.dll", EntryPoint="SendMessageA")]private static extern int SendMessage (IntPtr hwnd, int wMsg, IntPtr wParam, string lParam);[DllImport("user32.dll", EntryPoint="SendMessageA")]private static extern int SendMessage (IntPtr hwnd, int wMsg, IntPtr wParam, ref Rectangle lParam);//调用:string s = "hello, floodzhu";SendMessage(this.textBox1.Handle, WM_SETTEXT, IntPtr.Zero, s);Rectangle rect = new Rectangle();SendMessage(this.richTextBox1.Handle, EM_GETRECT, (IntPtr)0, ref rect);
● 对要求返回字符串的类型(out string)可以用 StringBuilder 代替,此时不需要 out/ref。例如:
[DllImport("user32.dll", EntryPoint="SendMessageA")]private static extern int SendMessage (IntPtr hwnd, int wMsg, int wParam, StringBuilder lParam);private void button1_Click(object sender, System.EventArgs e){ const int buffer_size = 1024; StringBuilder buffer = new StringBuilder(buffer_size); SendMessage(this.textBox1.Handle, WM_GETTEXT, buffer_size, buffer); //MessageBox.Show(buffer.ToString());}
● 如果想用 InPtr 类型统一处理的话,可以借助于 Marshal 或者 GCHandle 的相关方法。例如:
[DllImport("user32.dll", EntryPoint="SendMessageA")]private static extern int SendMessage (IntPtr hwnd, int wMsg, IntPtr wParam, IntPtr lParam);private void button2_Click(object sender, System.EventArgs e){ Rectangle rect = new Rectangle(); IntPtr buffer = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(Rectangle))); Marshal.StructureToPtr(rect, buffer ,true); SendMessage(this.richTextBox1.Handle, EM_GETRECT, (IntPtr)0, buffer); rect = (Rectangle)Marshal.PtrToStructure(buffer, typeof(Rectangle)); Marshal.FreeHGlobal(buffer);}
或者
private void button2_Click(object sender, System.EventArgs e){ Rectangle rect = new Rectangle(); GCHandle gch = GCHandle.Alloc(rect); SendMessage(this.richTextBox1.Handle, EM_GETRECT, (IntPtr)0, (IntPtr)gch); rect = (Rectangle)Marshal.PtrToStructure((IntPtr)gch, typeof(Rectangle)); gch.Free();}