介绍：

　　该程序本意是为了在彩六里打中文用的，现整理出来供大家复制粘贴。

　　主要使用SendInput函数，与c语言中用法一致。（部分代码来自网络）

命名空间部分

using static System.Threading.Thread;
using System.Runtime.InteropServices;

结构体和函数声明部分

[StructLayout(LayoutKind.Explicit)]
        public struct INPUT
        {
            [FieldOffset(0)]
            public int type;
            [FieldOffset(4)]
            public KEYBDINPUT ki;
            [FieldOffset(4)]
            public MOUSEINPUT mi;
            [FieldOffset(4)]
            public HARDWAREINPUT hi;
        }
        public struct MOUSEINPUT
        {
            public int dx;
            public int dy;
            public int mouseData;
            public int dwFlags;
            public int time;
            public IntPtr dwExtraInfo;
        }
        public struct KEYBDINPUT
        {
            public short wVk;
            public short wScan;
            public int dwFlags;
            public int time;
            public IntPtr dwExtraInfo;
        }
        public struct HARDWAREINPUT
        {
            public int uMsg;
            public short wParamL;
            public short wParamH;
        }

        [DllImport("user32")]
        public static extern uint SendInput(uint nInputs, INPUT[] pInputs, int cbSize);

自定义函数封装部分

public void SimulateInputString(char c)
        {
            INPUT[] input = new INPUT[2];
                
            input[0].type = 1;
            input[0].ki.wVk = 0;//dwFlags 为KEYEVENTF_UNICODE 即4时，wVk必须为0
            input[0].ki.wScan = (short)c;
            input[0].ki.dwFlags = 4;//输入UNICODE字符
            input[0].ki.time = 0;
            input[0].ki.dwExtraInfo = IntPtr.Zero;
            input[1].type = 1;
            input[1].ki.wVk = 0;
            input[1].ki.wScan = (short)c;
            input[1].ki.dwFlags = 6;
            input[1].ki.time = 0;
            input[1].ki.dwExtraInfo = IntPtr.Zero;
            SendInput(2u, input, Marshal.SizeOf((object)default(INPUT)));
            
        }

        public void SimulateInputKey(int key)
        {
            INPUT[] input = new INPUT[1];

            input[0].type = 1;//模拟键盘
            input[0].ki.wVk = (short)key;
            input[0].ki.dwFlags = 0;//按下
            SendInput(1u, input, Marshal.SizeOf((object)default(INPUT)));
            Sleep(50);

            input[0].type = 1;//模拟键盘
            input[0].ki.wVk = (short)key;
            input[0].ki.dwFlags = 2;//抬起
            SendInput(1u, input, Marshal.SizeOf((object)default(INPUT)));
            Sleep(50);
        }

说明：

SimulateInputString为发送单个字符文本；

SimulateInputKey为模拟按键按下和抬起，参数key为虚拟键码；

关于键码的列表，可以查看微软文档：https://docs.microsoft.com/en-us/windows/win32/inputdev/virtual-key-codes