受付のJS

reception.js

function slack() {
        let xmlhttp = new XMLHttpRequest();
        let webhook_url = 'https://hooks.slack.com/services/******/******';
        let message = '{"username": "受付" ,"text":"受付でボタンが押されました",  "icon_emoji": ":office:"}';
        xmlhttp.open('POST', webhook_url, false);
        xmlhttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
        xmlhttp.send(message);
        location.href='reception2.html';
    }