C# Console：利用mspaint打开图像并保存 。

System.Diagnostics.Process process = new System.Diagnostics.Process();
process = System.Diagnostics.Process.Start("mspaint.exe", path);
int processId = process.Id;

AutomationElement element = FindWindowByProcessId(processId);
System.Windows.Forms.SendKeys.SendWait("^s");       //发送 Ctrl + s 键
System.Windows.Forms.SendKeys.SendWait("%{F4}");      // 发送 Alt + F4 键

        public static AutomationElement FindWindowByProcessId(int processId)
        {
            AutomationElement targetWindow = null;
            int count = 0;
            try
            {
                Process p = Process.GetProcessById(processId);
                targetWindow = AutomationElement.FromHandle(p.MainWindowHandle);
                return targetWindow;
            }
            catch (Exception ex)
            {
                count++;
                StringBuilder sb = new StringBuilder();
                string message = sb.AppendLine(string.Format("Target　window　is　not　existing.try　#{0}", count)).ToString();
                if (count > 5)
                {
                    throw new InvalidProgramException(message, ex);
                }
                else
                {
                    return FindWindowByProcessId(processId);
                }
            }
        }

SendKeys.SendWait("{F5}");          //发送F5按键
SendKeys.SendWait("^s");       //发送 Ctrl + s 键
SendKeys.SendWait("%{F4}");      // 发送 Alt + F4 键

//按键 代码 
BACKSPACE {BACKSPACE}, {BS}, 或 {BKSP} 
BREAK {BREAK} 
CAPS LOCK {CAPSLOCK} 
DEL or DELETE {DELETE} 或 {DEL} 
DOWN ARROW {DOWN} 
END {END} 
ENTER  {ENTER}或 ~ 
ESC {ESC} 
HELP {HELP} 
HOME {HOME} 
INS or INSERT {INSERT} 或 {INS} 
LEFT ARROW {LEFT} 
NUM LOCK {NUMLOCK} 
PAGE DOWN {PGDN} 
PAGE UP {PGUP} 
PRINT SCREEN {PRTSC} 
RIGHT ARROW {RIGHT} 

SendKeys.SendWait("+{TAB}");
SendKeys.SendWait("%f");//alt+f
SendKeys.SendWait("{Tab}");
SendKeys.SendWait("{Enter}")

//多次按键的代码


//为了指定重复键，使用 {key number} 的形式。必须在 key 与 number 之间放置一个空格。//例如，{LEFT 42} 意指 42 次按下 LEFT ARROW 键；{h 10} 则是指 10 次按下 H 键。

Where is the System.Windows.Automation

The UIAutomationClient.dll is located in this folder:

C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0

If you can't find in your Add Reference->.Net tab, then you have to use the Browse tab to go to the given path, and add the assembly (Right Click on the References, choose add reference, click browse tab):

 

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