ReactJS . Post JSON data by onClick

    handleClick() {

        var array = [];

        var elements = document.getElementsByClassName('checkTask');
        for (var i = 0; i < elements.length; i++) {
            var p = elements[i].getAttribute('checked');

            if (p === 'checked') {

                var folder = elements[i].getAttribute('data-folder');
                var name = elements[i].getAttribute('data-name');
                var description = elements[i].getAttribute('data-description');
                var key = elements[i].getAttribute('data-key');
                var created = elements[i].getAttribute('data-created');
                array.push({
                    "Folder": folder,
                    "Name": name,
                    "description": description,
                    "key": key,
                    "created": created
                });
            }
        }
        var data = JSON.stringify(array);
        var RunTaskRequest = new Request('api/TasksData/AddToQueue', {
            method: 'POST',
            body: data,
            headers: {
                Accept: 'application/json',
                'Content-Type': 'application/json',
            }
        });

        let fetchTask = fetch(RunTaskRequest)
            .then((response) => response.json())
            .then((responseJson) => {
                responseJson.map((taskItem: any) => {

                    var Key = taskItem.Key;

                    var node = document.getElementById(Key);
                    if (node) {
                        while (node.hasChildNodes()) {
                            if (node.lastChild)
                                node.removeChild(node.lastChild);
                        }

                        var img = document.createElement("img");
                        img.src = "/images/waiting.png";
                        img.title = "Waiting to run";
                        var nodeInsert = img.cloneNode();
                        node.appendChild(nodeInsert);

                        var key = "row_chk" + Key;
                        var rowElement = document.getElementById(key);
                        if (rowElement != null) {
                            var stateClasses = rowElement.className;
                            var stateClasses = stateClasses.replace(' ' + 'selected_row', "");
                            rowElement.className = stateClasses;
                        }

                    }

                })

            })
            .catch((error) => {
                console.error(error);
            });
    }