js每5秒发送一个请求 40s后结束

const started = Date.now();

this.interval = setInterval( () => {
    //40秒后 清除事件
	if ( 40000 <= Date.now() - started ) {
		clearInterval( this.interval );
	} else {
	const ajaxurl = '';
	const data = {};
		$.post( ajaxurl, data )
			.done( response => {})
			.fail( jqXHR => {});
		}
}, 5000 ); //每5秒发送一次请求，发送第一次请求前会等待5秒