How to read JSON data sent to my asp.net page (callback url) from gateway

Question

Okay My question is likewise: I am implementing a crypto payment gateway, I send all parameters along with callbackurl (which is notification url). Once I make payment, it will send a notification in json format. I don't know how to read data/parse data without knowing source url which is sending notification to my notification url.

the data likewise:

{
  "timestamp": 6716171771,
  "nonce": 5635262,
  "sign": "dasjh1276312hjhdwwghhdsuy2128781291g2",
  "body": "{\"address\":\"01HSXHSUSGNXSHGDSKJDASJ\",\"amount\":\"7917\",\"blockHigh\":\"17219\",\"coinType\":\"206\",\"decimals\":\"8\",\"fee\":\"452000\",\"mainCoinType\":\"206\",\"status\":3,\"tradeId\":\"20181024175416907\",\"tradeType\":1,\"txId\":\"31689c332536b56a2246347e206fbed2d04d461a3d668c4c1de32a75a8d436f0\"}"
}

string result_GET = null;
string url = "https://mytestweb.com/notifypayment.aspx";
// I don't know what URL we use here in case we don't know the source url, so this is my general practice for all gateways GET response.
WebResponse response = null;
StreamReader reader = null;


HttpWebRequest httpWebRequest = null;
httpWebRequest = HttpWebRequest.Create(url) as HttpWebRequest;
httpWebRequest.Method = "GET"; // Supports POST too


var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
    var get_json_data = streamReader.ReadToEnd();
    LabelJsonData.Text = get_json_data.ToString();

    //I want the json data here , so that I can parse it and use it then.

}

Answer 1

As far as I can tell you are just trying to handle JSON data.

With C# there are two main options you have, there may be others. I have used both in the past.

The Microsoft one: https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/how-to?pivots=dotnet-8-0

The NewtonSoft one: https://www.newtonsoft.com/json

Unless you need anything found in the NewtonSoft option, you may be better off using the microsoft one. That is just my oppinion. Both work well and I have no problem with either. The reason for this advise is the microsoft one is part of whats available and you don't need to use anything extra.

This is some information about serialisation/deserialistion of JSON you might find useful : What is deserialize and serialize in JSON?

If you know the structure of the JSON data (which I think you do) you can create a class structure to deserialise the JSON into using generics. Or you can use without the a specific class structure to hold the convert json.

I am showing C# 7 related code from (https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/how-to?pivots=dotnet-7-0)

The example below is when you don't have a class structure.

using System;
using System.Text.Json;

string jsonString = "{\"name\":\"John Doe\",\"age\":30}";

JsonDocument jsonDocument = JsonDocument.Parse(jsonString);

foreach (JsonProperty element in jsonDocument.RootElement.EnumerateObject())
{
    Console.WriteLine($"Property Name: {element.Name}");
    Console.WriteLine($"Property Value: {element.Value}");
}

The other way is to use a class structure like this

Say you have this class (which matches the expected JSON)

public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
}

Where the JSON is

{
    "name": "John Doe",
    "age": 30
}

You can use this code

using System.Text.Json;

string jsonString = "{\"name\":\"John Doe\",\"age\":30}";

Person person = JsonSerializer.Deserialize<Person>(jsonString);

Console.WriteLine(person.Name); // Output: John Doe
Console.WriteLine(person.Age); // Output: 30

In the above code samples the jsonString would be get_json_data.ToString()

Obviously the C# classes are not the right ones for the JSON you have and are illustrative. So you will need to decide on which approach you want to use. The class option is nice, but you will need to write the appropriate class to support your own JSON structure.