How to use the roosterjs-editor-api.toggleHeader function in roosterjs-editor-api

function _handleChangeForHeader(editor: Editor, props: RoosterCommandBarProps, state: RoosterCommandBarState): void {
    if (state.formatState.headerLevel === this.headerLevel) {
        toggleHeader(editor, 0);
    } else {
        toggleHeader(editor, this.headerLevel);
    }
}

document.getElementById('header').addEventListener('change', function() {
        let select = document.getElementById('header') as HTMLSelectElement;
        let level = parseInt(select.value);
        toggleHeader(getCurrentEditor(), level);
        select.value = '-1';
    });

        onClick: (editor, value) => toggleHeader(editor, parseInt(value)),
        dropDownItems: {

function _handleChangeForHeader(editor: Editor, props: RoosterCommandBarProps, state: RoosterCommandBarState): void {
    if (state.formatState.headerLevel === this.headerLevel) {
        toggleHeader(editor, 0);
    } else {
        toggleHeader(editor, this.headerLevel);
    }
}