方法一：

using System.Diagnostics; 


Process[] vProcesses = Process.GetProcesses(); 
foreach (Process vProcess in vProcesses) 
if (vProcess.ProcessName.Equals( "iexplore ", 
StringComparison.OrdinalIgnoreCase)) 
{ 
MessageBox.Show( "IE已經開啟 "); 
break; 
}


方法二：

using System.Diagnostics;


Process[] app = Process.GetProcessesByName("AMS");
            if (app.Length > 0)
            {
                MessageBox.Show("請關閉已經啟動的程式後再進行嘗試");
                return;
            }
            else
            {
                System.Diagnostics.Process.Start("AMS.exe");
            }


殺死程序：查詢到對應的程序後就可以呼叫系統命令殺死指定名稱的程序

            Process[] p = Process.GetProcessesByName("AMS");
            foreach (Process ps in p)
            {
                ps.Kill();
            }
 

啟動

用Process類
Process[] myprocess=Process.GetProcessesByName("a");
if(myprocess.length>0)
{
    myprocess[0]. CloseMainWindow();
    myprocess[0].Close();
}
else
{
    Process.Start("a.exe");
}