The type 'System.Int32[,]' is not supported.

[Sc7-git]

Description

            int[,] array2D = new int[,] { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } };
            var array2DJson= System.Text.Json.JsonSerializer.Serialize(array2D);
            var json = "[[\"uhhvle7p55hc\",\"uhhvle7p55hd\",\"uhhvle7p55hh\"]]";
            var array = System.Text.Json.JsonSerializer.Deserialize<string[,]>(json);

Reproduction Steps

            int[,] array2D = new int[,] { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } };
            var array2DJson= System.Text.Json.JsonSerializer.Serialize(array2D);
            var json = "[[\"uhhvle7p55hc\",\"uhhvle7p55hd\",\"uhhvle7p55hh\"]]";
            var array = System.Text.Json.JsonSerializer.Deserialize<string[,]>(json);

Expected behavior

Return serialization result

Actual behavior

The type 'System.Int32[,]' is not supported.

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

[ghost]

Tagging subscribers to this area: @dotnet/area-system-text-json, @gregsdennis See info in area-owners.md if you want to be subscribed.

Issue Details

---

### Description ``` int[,] array2D = new int[,] { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } }; var array2DJson= System.Text.Json.JsonSerializer.Serialize(array2D); var json = "[[\"uhhvle7p55hc\",\"uhhvle7p55hd\",\"uhhvle7p55hh\"]]"; var array = System.Text.Json.JsonSerializer.Deserialize(json); ``` ### Reproduction Steps ``` int[,] array2D = new int[,] { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } }; var array2DJson= System.Text.Json.JsonSerializer.Serialize(array2D); var json = "[[\"uhhvle7p55hc\",\"uhhvle7p55hd\",\"uhhvle7p55hh\"]]"; var array = System.Text.Json.JsonSerializer.Deserialize(json); ``` ### Expected behavior Return serialization result ### Actual behavior The type 'System.Int32[,]' is not supported. ### Regression? _No response_ ### Known Workarounds _No response_ ### Configuration _No response_ ### Other information _No response_

Author:	Sc7-git
Assignees:	-
Labels:	`area-System.Text.Json`
Milestone:	-

[huoyaoyuan]

Duplicate of #44347. Currently there's no support for MD array.

[gregsdennis]

Three years later, and STJ is significantly more mature. Can we use this issue to have another look at implementing it?

Not sure what a JSON representation of a MD array would look like, though. I wonder if there are any precedents.

[eiriktsarpalis]

Not sure what a JSON representation of a MD array would look like, though.

There doesn't appear to be a standard representation being used anywhere, although using jagged arrays is probably the safest (although likely not the most efficient) representation. I found this article discussing various approaches.

[m-gallesio]

There doesn't appear to be a standard representation being used anywhere, although using jagged arrays is probably the safest (although likely not the most efficient) representation.

Newtonsoft.Json does this too:

int[,] matrix = new int[2, 3]
{
    { 1, 2, 3 },
    { 4, 5, 6 }
};
System.Console.WriteLine(Newtonsoft.Json.JsonConvert.SerializeObject(matrix));

[[1,2,3],[4,5,6]]