using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Diagnostics;using System.IO;using System.Runtime.InteropServices;namespace WfpApp{ class PositionNotepad { [DllImport("User32.dll", EntryPoint = "FindWindow")] private static extern IntPtr FindWindow(string lpClassName, string lpWindowName); [DllImport("user32.dll")] static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string lpszClass, string lpszWindow); [DllImport("user32.dll")] static extern bool SetForegroundWindow(IntPtr hWnd); ///<summary>   /// 定位到txt文件指定行   ///</summary>   ///<param name="strFullName">文件路徑</param>   ///<param name="strRow">指定行</param>   ///<returns>定位是否成功</returns>   public static bool PositionNotePad(string strFullName, string strRow) {  int iRow;  int.TryParse(strRow, out iRow);  if (iRow <= 0)  {  return false;  }  //查看當前文件是否已打開   IntPtr hwnd = FindWindow("Notepad", string.Format("{0} - 記事本", Path.GetFileName(strFullName)));  if (hwnd.ToInt32() == 0)  {  Process p = Process.Start(@"notepad.exe", strFullName);  //等一秒，等文本打開，焦點去到notepad  p.WaitForInputIdle(1000);  System.Windows.Forms.SendKeys.SendWait("{DOWN " + (iRow - 1) + "}");  System.Windows.Forms.SendKeys.SendWait("{HOME}"); //行首  System.Windows.Forms.SendKeys.SendWait("+{END}"); //選中當前行  return true;  }  else  {  hwnd = FindWindowEx(hwnd, IntPtr.Zero, "Edit", string.Empty);  if (hwnd.ToInt32() == 0)   return false;  else  {   SetForegroundWindow(hwnd);   System.Windows.Forms.SendKeys.SendWait("^{HOME}");//將光標定位到首行   System.Windows.Forms.SendKeys.SendWait("{DOWN " + (iRow - 1) + "}");   System.Windows.Forms.SendKeys.SendWait("{HOME}"); //行首   System.Windows.Forms.SendKeys.SendWait("+{END}"); //選中當前行  }  }  return true; } }}

string path = @"C:/Users/ZKK/Desktop/English.txt";bool res = PositionNotepad.PositionNotePad(path, "5");