1.C# 调用python

本质上是使用命令行运行python

1.1 C# 使用命令行

program.cs

using System;
using System.Diagnostics;
using System.IO;namespace test
{class Program{static void Main(string[] args){Program p = new Program();string result = p.run_cmd("ping.exe", "8.8.8.8 -n 2");Console.WriteLine(result);Console.ReadKey();}public string run_cmd(string program, string cmd){ProcessStartInfo start = new ProcessStartInfo();start.FileName = program;start.Arguments = cmd;start.UseShellExecute = false;          // Do not use OS shellstart.CreateNoWindow = true;            // We don't need new windowstart.RedirectStandardOutput = true;    // Any output, generated by application will be redirected backstart.RedirectStandardError = true;     // Any error in standard output will be redirected back (for example exceptions)using (Process process = Process.Start(start)){using (StreamReader reader = process.StandardOutput){string result = process.StandardError.ReadToEnd();if (result == null || result == ""){result = reader.ReadToEnd();}return result;}}}}
}

代码运行结果 

• 调用run_cmd相当于执行了cmd命令，所以就有了使用命令行运行python脚本的方式

1.2. C# 调用 python3脚本

假设C盘根目录下有如下脚本 test1.py

import sysdef add(a,b):return a+bif __name__ == "__main__":print(sys.argv[1])print("hello python")

在 program.cs 中加入函数runPython，并修改main函数

static void Main(string[] args)
{Program p = new Program();//string result = p.run_cmd("ping.exe", "8.8.8.8 -n 2");string result = p.runPython("C:\\test1.py", "\"Form C#:\"");Console.WriteLine(result);Console.ReadKey();
}public string runPython(string filename, string cmd)
{string cmd1 = string.Format("{0} {1}", filename, cmd);return run_cmd("python.exe", cmd1);
}

代码运行结果 

1.3 C# 调用python3内的函数

我们知道使用python -c可以直接执行python代码，所以合理构造语句就可以直接调用python脚本内的函数了：python -c "print('hello python')"。 
若要调用脚本里的函数，常规写法为：

import sys
sys.path.append('c:\\')
import test1
print(test1.add(3,4))

缩成一行就是python -c "import sys;sys.path.append('c:\\');import test1;print(test1.add(3,4))"

在 program.cs 中加入函数runPyFunc，并修改main函数

        static void Main(string[] args){Program p = new Program();//string result = p.run_cmd("ping.exe", "8.8.8.8 -n 2");//string result = p.runPython("C:\\test.py", "\"Form C#:\"");string result = p.runPyFunc(@"C:\\","test1","add","3,4");Console.WriteLine(result);Console.ReadKey();}public string runPyFunc(string path, string filename, string functionname, string parameter){string cmd = string.Format("-c \"import sys;sys.path.append('{0}');import {1};print({1}.{2}({3}))\"", path, filename, functionname, parameter);return run_cmd("python.exe", cmd);}

运行就可以得到结果“7”了