Sending List in http request in C#

Question

I'm trying to send List (of strings) as http request to a flask python backend but I cant figure how to parse the list into json format to send that

I tryed this:

var myObject = (dynamic)new JsonObject();
myObject.List = new List<string>();
// add items to your list

according to this: C# HTTP post , how to post with List<XX> parameter? but It's says that List isn't recognized. any help or other method to do this?

First, read about a technology completely, then if you encounter a problem, ask a question. It is clear that you do not know the basic points , such as `serialization` and `deserialization`. — Mohammad Aghazadeh, Dec 21 '22 at 10:20

score 3 · Answer 1 · answered Dec 21 '22 at 10:26

Use JsonSerializer in order to convert any object to a string

var list = new List<string>();
httpClient.PostAsync(
    "",
    new StringContent(
        System.Text.Json.JsonSerializer.Serialize(list),
        Encoding.UTF8,
        "application/json"));

If you need to send an object with a List property:

var list = new List<string>();
httpClient.PostAsync(
    "",
    new StringContent(
        System.Text.Json.JsonSerializer.Serialize(new {List = list}),
        Encoding.UTF8,
        "application/json"));

score 0 · Accepted Answer · answered Dec 21 '22 at 10:25

please prefer this Microsoft documentation.

https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/how-to?pivots=dotnet-7-0

using System.Text.Json;

namespace SerializeToFile
{
public class WeatherForecast
{
    public DateTimeOffset Date { get; set; }
    public int TemperatureCelsius { get; set; }
    public string? Summary { get; set; }
}

public class Program
{
    public static void Main()
    {
        var weatherForecast = new WeatherForecast
        {
            Date = DateTime.Parse("2019-08-01"),
            TemperatureCelsius = 25,
            Summary = "Hot"
        };

        string fileName = "WeatherForecast.json"; 
        string jsonString = JsonSerializer.Serialize(weatherForecast);
        File.WriteAllText(fileName, jsonString);

        Console.WriteLine(File.ReadAllText(fileName));
    }
}
}
// output:
//{"Date":"2019-08-01T00:00:00- 
07:00","TemperatureCelsius":25,"Summary":"Hot"}

Sending List in http request in C#

2 Answers2