How do I deserialize json arrays from url in C# ?

Question

0.00/5 (No votes)

See more:

I have been trying to deserialize a json data from wordpress url but didn t work.
I saw many tutorials but no one worked on mine !

This is my URL : https://mahdii.000webhostapp.com/?wpapi=get_posts&amp;dev=1[^]

I am getting Null in var serialized_post.

Please I need Help

What I have tried:

I have tried to deserialize using this code :

string json = new WebClient().DownloadString("https://mahdii.000webhostapp.com/?wpapi=get_posts&dev=1");
Console.WriteLine(json);
var deserialize_post = JsonConvert.DeserializeObject<List<mycontainer>>(json);

My Class:

namespace App8
{
    public class Author
    {
        public string id { get; set; }
        public string slug { get; set; }
        public string name { get; set; }
        public string first_name { get; set; }
        public string last_name { get; set; }
        public string nickname { get; set; }
        public string url { get; set; }
        public string description { get; set; }
        public string gravatar { get; set; }
    }

    public class Post
    {
        public string id { get; set; }
        public string type { get; set; }
        public string slug { get; set; }
        public string url { get; set; }
        public string status { get; set; }
        public string title { get; set; }
        public string title_plain { get; set; }
        public string date { get; set; }
        public string modified { get; set; }
        public string excerpt { get; set; }
        public string parent { get; set; }
        public List<object> category { get; set; }
        public List<object> tag { get; set; }
        public List<Author> author { get; set; }
        public string comment_count { get; set; }
        public string comment_status { get; set; }
    }

    public class MyContainer
    {
        
        public List<Post> posts { get; set; }
    }
}

Posted 12-Feb-17 8:05am

Member 12468321

Updated 12-Feb-17 8:42am

Patrice T

v5

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Afzaal Ahmad Zeeshan · Accepted Answer · 2017-02-12T08:42:00

One single reason: Because you are not doing it correctly. You are deserializing it to a "list of list of posts". And your JSON is a "document containing posts". I could write something as simple as,

C#

// Skip compile time type checking, first. 
dynamic deserialize_post = JsonConvert.DeserializeObject(json);

if(deserialize_post.posts != null) {
   // check if posts exist
   List<Post> posts = deserialize_post.posts;

   // Do further processing.
}

// Do the same for author etc.

Now, the problem mainly is that when the data comes from an API, you either need to map it back to the "exact" same copy of the object, or you cannot map it anywhere. You may have also seen that I used, "posts", instead of "Posts". That is because, the case also matters a lot in this case. In the case, where you are downloading the data from an API, it is recommended to always use dynamic as you may not know what is being shipped and what is not and you then check it on the runtime; dynamic skips compile time type checking, but to make sure data exists, we use if...else branching to load the data, or show an error message if the data does not exist.

For more on this, please read my article, From zero to hero in JSON with C#[^] and specially an answer at the bottom of the article that talks specifically about this problem.