c# – Doubt with string, extract data

Question:

I have the following string

[{"tipo":"simnao","pergunta":"rwerwerwerewr ?","tag":"#acimadopeso","resposta":"","$$hashkey":"object:410"},{"pergunta":"werwerwerwer ?","tag":"#diabetes","resposta":"","$$hashkey":"object:412"},{"pergunta":"werwerwer ?","tag":"#idoso","resposta":"","$$hashkey":"object:414"}]

I need to extract to a list only the words that contain the "#", or else I need to put the words #acimadopeso and #diabetes in a List . how can I do this?

Answer:

As this is a JSON I recommend using the Json.NET Newtonsoft library to get the data you want.

Just parse it using the JArray class and in a foreach get the key tag values ​​so you can fill your string list, for example:

using System;
using System.Collections.Generic;
using Newtonsoft.Json.Linq;

public class Program
{
    public static void Main()
    {
        var json = "[{\"tipo\":\"simnao\",\"pergunta\":\"rwerw#erwerewr ?\",\"tag\":\"#acimadopeso\",\"resposta\":\"\",\"$$hashkey\":\"object:410\"},{\"pergunta\":\"werwerwerwer ?\",\"tag\":\"#diabetes\",\"resposta\":\"\",\"$$hashkey\":\"object:412\"},{\"pergunta\":\"werwerwer ?\",\"tag\":\"#idoso\",\"resposta\":\"\",\"$$hashkey\":\"object:414\"}]";     
        JArray array = JArray.Parse(json);      
        var tags = new List<string>();      
        foreach (var a in array)
            tags.Add(a["tag"].ToString());      
    }
}

Output tags.ForEach(x => Console.WriteLine(x));

#acimadopeso
#diabetes
#idoso

See working in .NET Fiddle .