有没有办法使用标准输入/输出流来传递C＃和R？

I want to build a C# program that is needed to communicate with R (rscript.exe) via standard input/output stream. But I can't find a way to write anything into rscript's input stream.

我想构建一个通过标准输入/输出流与R（rscript.exe）通信所需的C＃程序。但我找不到在rscript的输入流中写任何东西的方法。

Here is the C# program that uses a Process whose streams are redirected.

这是使用其流被重定向的进程的C＃程序。

using System;
using System.Collections.Generic;
using System.Diagnostics;

namespace test1
{
    class Program
    {        
        static void Main(string[] args)
        {
            var proc = new Process();
            proc.StartInfo = new ProcessStartInfo("rscript", "script.R") 
            {
                RedirectStandardInput = true,
                RedirectStandardOutput = true,
                UseShellExecute = false
            };

            proc.Start();            

            var str = proc.StandardOutput.ReadLine();

            proc.StandardInput.WriteLine("hello2");

            var str2 = proc.StandardOutput.ReadToEnd();

        }
    }
}

Here is script.R:

这是script.R：

cat("hello\n")

input <- readline()

cat("input is:",input, "\n")

str is able to capture "hello" but "hello2" can't be written into R's stream so that str2 always gets "\r\ninput is: \r\n".

str能够捕获“hello”但是“hello2”不能写入R的流中，因此str2总是得到“\ r \ ninin输出：\ r \ n”。

Is there a way to write texts into R's input stream in this way?

有没有办法以这种方式将文本写入R的输入流？

1 个解决方案

#1

The answer in https://*.com/a/9370949/2906900 works for this question.

https://*.com/a/9370949/2906900中的答案适用于此问题。

Here's an minimal example in which C# and rscript.exe interact through stdio.

这是一个最小的例子，其中C＃和rscript.exe通过stdio进行交互。

In the R script, stdin connection must be explicitly open.

在R脚本中，必须显式打开stdin连接。

R code:

R代码：

f <- file("stdin")
open(f)
input <- readLines(f, n = 1L)
cat("input is:", input)

In this case, the input stream of rscript can be accessed.

在这种情况下，可以访问rscript的输入流。

C# code:

C＃代码：

using System;
using System.Collections.Generic;
using System.Diagnostics;

namespace test1
{
    class Program
    {        
        static void Main(string[] args)
        {
            var proc = new Process();
            proc.StartInfo = new ProcessStartInfo("rscript")
            {
                Arguments = "script.R",
                RedirectStandardInput = true,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                UseShellExecute = false
            };

            proc.Start();
            proc.StandardInput.WriteLine("Hello");
            var output = proc.StandardOutput.ReadLine();
            Console.WriteLine(output);
        }
    }
}

#1