从C#调用Python脚本遇‘获取Python编解码器失败’致命错误的解决方法

问题场景 #

通过C#的Process类调用本地Python 3.10脚本，脚本单独运行正常，但C#调用时出现Python编码相关的致命错误，无法正常执行。

相关代码 #

C#调用代码 #

static string CallPython(string fileName)
{
    Process p = new Process();
    p.StartInfo = new ProcessStartInfo(@"C:\Python310\python.exe", fileName)
    {
        RedirectStandardOutput = true,
        UseShellExecute = false,
        CreateNoWindow = true
    };
    p.Start();

    string output = p.StandardOutput.ReadToEnd();
    p.WaitForExit();

    return output;
}

Python脚本 #

Print("It worked?")

错误信息 #

Python path configuration:
  PYTHONHOME = (not set)
  PYTHONPATH = (not set)
  program name = 'C:\Python310\python.exe'
  isolated = 0
  environment = 1
  user site = 1
  import site = 1
  sys._base_executable = 'C:\\Python310\\python.exe'
  sys.base_prefix = 'C:\\Python310'
  sys.base_exec_prefix = 'C:\\Python310'
  sys.platlibdir = 'lib'
  sys.executable = 'C:\\Python310\\python.exe'
  sys.prefix = 'C:\\Python310'
  sys.exec_prefix = 'C:\\Python310'
  sys.path = [
    'C:\\Python310\\python310.zip',
    'C:\\Python310\\DLLs',
    'C:\\Python310\\lib',
    'C:\\Python310',
  ]
Fatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding
Python runtime state: core initialized
Traceback (most recent call last):
  File "C:\Python310\lib\encodings\__init__.py", line 33, in <module>
ImportError: cannot import name 'aliases' from partially initialized module 'encodings' (most likely due to a circular import) (C:\Python310\lib\encodings\__init__.py)
'PythonCallExperiment.exe' (CLR v4.0.30319: PythonCallExperiment.exe): Loaded 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\Common7\IDE\PrivateAssemblies\Runtime\Microsoft.VisualStudio.Debugger.Runtime.dll'. Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.

已尝试操作 #

• 将UseShellExecute设置为true，问题未解决
• 搜索类似错误未找到有效方案
• 因VDI环境权限限制，暂未尝试IronPython

可行解决方案 #

方案1：显式设置PYTHONHOME环境变量 #

修改C#代码，在启动Python进程时添加PYTHONHOME环境变量，指向Python安装目录，帮助Python正确定位核心模块：

static string CallPython(string fileName)
{
    Process p = new Process();
    var startInfo = new ProcessStartInfo(@"C:\Python310\python.exe", fileName)
    {
        RedirectStandardOutput = true,
        UseShellExecute = false,
        CreateNoWindow = true
    };
    // 添加PYTHONHOME环境变量
    startInfo.EnvironmentVariables["PYTHONHOME"] = @"C:\Python310";
    p.StartInfo = startInfo;
    
    p.Start();
    string output = p.StandardOutput.ReadToEnd();
    p.WaitForExit();

    return output;
}

方案2：修正Python脚本的大小写问题 #

Python是大小写敏感语言，Print需改为小写的print（若用户实际脚本为笔误）：

print("It worked?")

方案3：确认Python目录访问权限 #

在VDI环境中，确保C#进程拥有访问C:\Python310目录及其子目录（尤其是lib\encodings）的权限，避免因权限不足导致无法读取编码模块文件。

内容的提问来源于stack exchange，提问作者MNagy