Zig

JSON: Nested Array

See more JSON Examples

Here we have a JSON object that contains nested arrays. This example demonstrates how to access the contents of the nested arrays.

{
 "numbers" : [ 
    ["even", 2, 4, 6, 8], 
    ["prime", 2, 3, 5, 7, 11, 13] 
  ] }

Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

    const json = try chilkat.JsonObject.init();
    defer json.deinit();

    // This is the above JSON with whitespace chars removed (SPACE, TAB, CR, and LF chars).
    // The presence of whitespace chars for pretty-printing makes no difference to the Load
    // method.
    const json_str = "{ \"numbers\" : [ [\"even\", 2, 4, 6, 8], [\"prime\", 2, 3, 5, 7, 11, 13] ] }";

    json.load(json_str) catch {
        std.debug.print("{s}\n", .{try json.getLastErrorText(alloc)});
        return;
    };

    // Get the value of the "numbers" object, which is an array that contains JSON arrays.
    const outer_array = json.arrayOf("numbers") catch {
        std.debug.print("numbers array not found.\n", .{});
        return;
    };
    defer outer_array.deinit();

    const num_arrays = outer_array.getSize();
    var i: i32 = 0;

    i = 0;
    while (i < num_arrays) : (i += 1) {
        const inner_array = try outer_array.arrayAt(i);
        defer inner_array.deinit();

        // The first item in the innerArray is a string
        std.debug.print("{s}:\n", .{try inner_array.stringAt(alloc, 0)});

        const num_inner_items = inner_array.getSize();
        var j: i32 = 0;
        j = 1;
        while (j < num_inner_items) : (j += 1) {
            std.debug.print("  {d}\n", .{inner_array.intAt(j)});
        }
    }
}