Zig

Check if Integer Exists at JSON Path

Demonstrates how to get an integer value at a JSON path, and how to check to see if it exists. 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();

    // First build simple JSON..
    json.updateInt("test.abc", 100) catch {};

    json.setEmitCompact(false);
    std.debug.print("{s}\n", .{try json.emit(alloc)});

    // This is our JSON:
    // {
    //   "test": {
    //     "abc": 100,
    //   }
    // }

    const path = "test.notHere";

    // The call to IntOf will return 0, because it's not present.
    // But how do we know if it really was present, and the value was truly 0?
    const val = json.intOf(path);
    std.debug.print("val = {d}\n", .{val});

    // We cannot use LastMethodSuccess because LastMethodSuccess only applies
    // to methods that:
    // - return a string
    // - return a new Chilkat object, binary bytes, or a date/time.
    // - returns a boolean status where true = success and false = failed.
    // - returns an integer where failure is defined by a return value less than zero.
    // The IntOf method fits none of these requirements, and therefore the LastMethodSuccess
    // is not a valid indicator..
    var was_found: bool = json.getLastMethodSuccess();
    std.debug.print("wasFound = {} (not a valid indicator)\n", .{was_found});

    // Instead, if the returned value is 0, we can double-check to see if the member was truly there..
    if (val == 0) {
        was_found = json.hasMember(path);
        std.debug.print("wasFound = {}\n", .{was_found});
        if (was_found) {
            std.debug.print("The value was present and is 0.\n", .{});
        } else {
            std.debug.print("no member is present at test.notHere\n", .{});
        }
    } else {
        std.debug.print("val = {d}\n", .{val});
    }

    // Alternatively, you could check to see if the member exists beforehand..
    if (json.hasMember(path)) {
        std.debug.print("val = {d}\n", .{json.intOf(path)});
    } else {
        std.debug.print("no member at {s}\n", .{path});
    }
}