1 using System; 2 using System.Collections.Generic; 3 using System.Runtime.InteropServices; 4 using System.Windows.Forms; 5  6 namespace StringToImage 7 { 8     static class Program 9     {10         [DllImport("user32.dll")]11         public static extern IntPtr FindWindow(String classname, String title);12         [DllImport("user32.dll")]13         public static extern void SetForegroundWindow(IntPtr hwnd);14 15         [STAThread]16         static void Main()17         {18             Application.EnableVisualStyles();19             Application.SetCompatibleTextRenderingDefault(false);20 21             string p = System.Diagnostics.Process.GetCurrentProcess().ProcessName;22             System.Diagnostics.Process[] processes = System.Diagnostics.Process.GetProcessesByName(p);23             if (processes.Length < 2)24                 Application.Run(new Form1());25             else26             {27                 //MessageBox.Show("程序已经运行!", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information);28                 IntPtr ptr = FindWindow(null, "文字转换成图片");//"文字转换成图片"为对应窗体的Text值29                 if (ptr.ToString() != "0")//不等于0表示找到了窗体30                     SetForegroundWindow(ptr);31 32                 Application.Exit();33             }34         }35     }36 }