Ignore JSON types

Question

Hi,

I am using MySQL at backend and I have problems with two fields when using System.Text.Json

The fields are mobile which has a value for example = 026547388

and is_admin which has 0 or 1 (representing true or false in MySQL)

When I use the Microsoft Json I get the following error:

The JSON value could not be converted to System.Boolean. Path: $[0].is_admin | LineNumber: 0 | BytePositionInLine: 383.

my is_admin is declared like this:

public bool is_admin { get; set; }

and mobile is declared this way:

public int mobile { get; set; }

regarding mobile, field, if I set It as int then I will be losing the 0 at the left and my number will be 026547388

Kindly help

Thanks,
Jassim

Answer 1

One of simple approaches is shown in the next example:

class MyData  
{  
	[JsonIgnore]  
	public bool is_admin { get; set; }  
  
	[EditorBrowsable( EditorBrowsableState.Never )]  
	[JsonPropertyName( "is_admin" )]  
	public int is_admin_as_int  
	{  
		get  
		{  
			return is_admin ? 1 : 0;  
		}  
		set  
		{  
			is_admin = value != 0;  
		}  
	}  
  
	public string mobile { get; set; }  
}  
  
// sample usage:  
var data = new MyData { is_admin = true, mobile = "026547388" };  
string json = JsonSerializer.Serialize( data ); // {"is_admin":1,"mobile":"026547388"}  
MyData data2 = JsonSerializer.Deserialize<MyData>( json );  

See also the topics related to converters, for example: https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json-converters-how-to.

Answer 2

If you already tried the second suggestion (using custom converters), then check this example too:

UserDetails data1 = new UserDetails { user_id = 100, first_name = "John", is_active = false, is_admin = true, mobile = "026547388" };
var options = new JsonSerializerOptions { Converters = { new MyConverter( ) } };
string json = JsonSerializer.Serialize( data1, options );
// result: {"user_id":100,"first_name":"John","last_name":null,"is_admin":1,"is_active":0,"mobile":"026547388"}
UserDetails data2 = JsonSerializer.Deserialize<UserDetails>( json, options );

where:

public class UserDetails
{
    public int user_id { get; set; }
    public string first_name { get; set; }
    // . . .
    public bool is_admin { get; set; }
    public bool is_active { get; set; }

    public string mobile { get; set; }
}


public class MyConverter : JsonConverter<bool>
{
    public override bool Read(
        ref Utf8JsonReader reader,
        Type typeToConvert,
        JsonSerializerOptions options ) => Convert.ToBoolean( reader.GetInt16( ) );

    public override void Write(
        Utf8JsonWriter writer,
        bool value,
        JsonSerializerOptions options ) => writer.WriteNumberValue( Convert.ToInt16( value ) );
}

See the documentation for other details about converters.