JSON Serialization in C#
What is JSON Serialization in C#?
**JSON (JavaScript Object Notation) Serialization** is the process of converting C# objects into **JSON format** for easy storage, communication, and data exchange. It is commonly used in **REST APIs, web services, and configuration files**.
Key Features of JSON Serialization
- Lightweight and **human-readable** format.
- Used in **REST APIs, web applications, and NoSQL databases**.
- Supports **objects, lists, and complex data structures**.
- Fast serialization and deserialization compared to XML.
Serializing Objects to JSON
In C#, **JSON serialization** is performed using the **System.Text.Json.JsonSerializer** class.
Example: Serializing an Object to JSON
using System;
using System.Text.Json;
using System.IO;
class Person
{
public string Name { get; set; }
public int Age { get; set; }
}
// Writing JSON Data
class Program
{
static void Main()
{
Person person = new Person { Name = "Alice", Age = 28 };
string json = JsonSerializer.Serialize(person);
File.WriteAllText("person.json", json);
Console.WriteLine("Object serialized to JSON.");
}
}
// Output:
// Object serialized to JSON.
The **JsonSerializer.Serialize()** method converts an object into a JSON string and saves it to a file.
Deserializing JSON to Objects
JSON data can be **converted back into C# objects** using the **JsonSerializer.Deserialize()** method.
Example: Deserializing JSON Data to an Object
using System;
using System.Text.Json;
using System.IO;
class Person
{
public string Name { get; set; }
public int Age { get; set; }
}
// Reading JSON Data
class DeserializeExample
{
static void Main()
{
string json = File.ReadAllText("person.json");
Person person = JsonSerializer.Deserialize(json);
Console.WriteLine($"Name: {person.Name}, Age: {person.Age}");
}
}
// Output:
// Name: Alice, Age: 28
The **JsonSerializer.Deserialize()** method reads a JSON string and converts it back into a C# object.
Serializing and Deserializing Lists
JSON serialization also works with **lists of objects**.
Example: Serializing and Deserializing a List
using System;
using System.Collections.Generic;
using System.Text.Json;
using System.IO;
class Person
{
public string Name { get; set; }
public int Age { get; set; }
}
// Writing JSON List Data
class Program
{
static void Main()
{
List people = new List
{
new Person { Name = "Alice", Age = 28 },
new Person { Name = "Bob", Age = 35 }
};
string json = JsonSerializer.Serialize(people);
File.WriteAllText("people.json", json);
Console.WriteLine("List serialized to JSON.");
}
}
// Reading JSON List Data
class DeserializeExample
{
static void Main()
{
string json = File.ReadAllText("people.json");
List people = JsonSerializer.Deserialize>(json);
foreach (var person in people)
{
Console.WriteLine($"Name: {person.Name}, Age: {person.Age}");
}
}
}
// Output:
// List serialized to JSON.
// Name: Alice, Age: 28
// Name: Bob, Age: 35
JSON serialization allows storing and retrieving **lists of objects** efficiently.
Customizing JSON Serialization
JSON serialization can be customized using **JsonSerializerOptions** to format output.
Example: Customizing JSON Output
using System;
using System.Text.Json;
using System.Text.Json.Serialization;
class Person
{
public string Name { get; set; }
[JsonIgnore]
public int Age { get; set; } // This property will be ignored
}
// Writing JSON with Custom Options
class Program
{
static void Main()
{
Person person = new Person { Name = "Charlie", Age = 40 };
var options = new JsonSerializerOptions { WriteIndented = true };
string json = JsonSerializer.Serialize(person, options);
Console.WriteLine(json);
}
}
// Output (formatted JSON):
// {
// "Name": "Charlie"
// }
The **[JsonIgnore]** attribute hides properties during serialization.
Best Practices for JSON Serialization
- Use **JsonSerializerOptions** for formatting and readability.
- Mark sensitive properties with **[JsonIgnore]** to prevent exposure.
- Use **list serialization** for handling multiple objects efficiently.
- Avoid unnecessary **nested objects** to keep JSON lightweight.