c# Newtonsoft json: how to deserialize json and get raw strings for float fields-CodePudding

Consider json string:

var json = "{\"myfield\":5e-0000006}";

I want deserialize that json, and get field "myfield" as raw string. Example:

JToken tok = <Deserialize> // how do this??
var val = tok["myfield"].ToString(); // need get "5e-0000006"

I need get EXACT string value that was in origin string ("5e-0000006" in example, but it may be any correct float string).

CodePudding user response：

Since you want an exact string and the json you have actually is a number (which means 5e-0000006 will equal 5e-6) I would suggest using regex:

string json = "{\"myfield\":5e-0000006}";
Regex regex = new Regex("(?<=:)[^}] ");
string result = regex.Match(json).Value;

Explanation:

(?<=:) look behind for a colon (:)

[^}] match any character not being a right curly brace (}), one or more times.

That should give you the value as an exact string.

Update:

If you want to match based on the myfield variable, you can expand the regex to contain that information:

string json = "{\"myfield\":5e-0000006}";
Regex regex = new Regex("(?<=\"myfield\":)[^}] ");
string result = regex.Match(json).Value;

Now you will only get the line where you have \"myfield\" in front - in case you have many lines.

You can of course replace \"myfield\" with a variable, like this:

string json = "{\"myfield\":5e-0000006}";
string myvar = "myfield";
Regex regex = new Regex("(?<=\""   myvar   "\":)[^}] ");
string result = regex.Match(json).Value;

CodePudding user response：

With some info, and inspiration, from:

        static void Main(string[] args)
        {
            var json = "{\"myfield\":5e-0000006}";

            MyJson j = JsonConvert.DeserializeObject<MyJson>(json);
            string mf = j.myfield;
            Console.WriteLine(mf);
        }

        public class MyJson 
        {
            [JsonProperty("myfield")]
            public string myfield { get; set; }
        }

This will output: 5e-0000006

And I am still wondering why I am not using JRaw ...