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Asp.net – How to pass JSON Object as argument to python script via C# process?

I’m trying to pass JSON object to python script through process but the script receives the JSON object in a wrong format the keys of the object without double or single quotes like the following:

{path:C:\Users\user\Documents\myfile.txt,models:[{Id:5014,Name:e,Type:2},{Id:2,Name:r1,Type:1}]}

C# process code:

 var script = "D:\python\pythonscript.py";
 var objectJson = new ObjectJson()
 {
     path = "C:\Users\user\Documents\myfile.txt",
     models = models
 };

 var x = JsonConvert.SerializeObject(objectJson);
 Console.WriteLine(x);

 psi.Arguments = $""{script}" """{x}"""";
 Console.WriteLine(psi.Arguments);
 psi.UseShellExecute = false;
 psi.CreateNoWindow = true;
 psi.RedirectStandardOutput = true;
 psi.RedirectStandardError = true;

 var errors = "";
 var results = "";

 using (var process = Process.Start(psi))
 {
     errors = process.StandardError.ReadToEnd();
     results = process.StandardOutput.ReadToEnd();
     process.WaitForExit();
 }

Josn object in C# code is :

{"path":"C:\Users\user\Documents\myfile.txt","models":[{"Id":5014,"Name":"e","Type":2},{"Id":2,"Name":"r1","Type":1}]}

Python code gives me error at data.models that there is no attribute called models in data

dataObj = sys.argv[1]
data = json.loads(dataObj)
models = data.models

When passing process arguments like the following:

 psi.Arguments = $""{script}" "{x}"";

python script gives an error at line json.loads(dataObj) that json decoder can’t convert it to json cause it expect name between double quotes.

Any idea how to solve this?

Tags:

2

Answers


  1. Chosen as BEST ANSWER
    0

    I've passed the arguments as follows and I'm not sure that this is the best solution but it works

    psi.Arguments = $""{script}" "{JsonConvert.SerializeObject(x)}"";

  2. 0

    Try passing like below :

       List<Item> jsonObject = new List<Item>
    {
            
            new Item { Name = "key1", Value = "value1" },
            new Item { Name = "key2 ", Value = "value2" }
    };


    using Newtonsoft.Json;
   
    
    string jsonString = JsonConvert.SerializeObject(itemList, Formatting.Indented);

    In you process in C# try passing like below :

    ProcessStartInfo startInfo = new ProcessStartInfo
    {
        FileName = pythonPath,
        Arguments = $"{scriptPath} "{JsonConvert.SerializeObject(jsonString)}"", // Pass JSON string as an argument
        RedirectStandardOutput = true,
        UseShellExecute = false,
        CreateNoWindow = true
    };

    using (Process process = new Process { StartInfo = startInfo })
    {
        process.Start();
        process.WaitForExit();
    }

    In your python code :

    import sys
import json

json_string = sys.argv[1]

json_object = json.loads(json_string)

print(json_object['key1'])
print(json_object['key2'])

    Check if the values key1 and key2 were received without any error. If so you can create a class Serialize object in C# properly and pass it to the shell script.

    What happens is that python actually complains that it is not valid JSON. In your case This is NOT VALID :

        {
    "path":"C:\Users\user\Documents\myfile.txt",
    "models":[
       {"Id":5014,"Name":"e","Type":2},
       {"Id":2,"Name":"r1","Type":1}
      ]
    }

    This is VALID :

    {
  "path": "C:\Users\user\Documents\myfile.txt",
  "models": [
    {
      "Id": "5014",
      "Name": "e",
      "Type": "2"
    },
    {
      "Id": "2",
      "Name": "r1",
      "Type": "1"
    }
  ]
}
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