双击

// 双击 方案，会导致单击至少有200ms的延时

clickInterval = null;

document.getElementById("con").onclick = function (e) {
    clearTimeout(clickInterval)
    clickInterval = setTimeout(function (e) {

        xy = getXY(e);
        if (xy === null)
            return;
        r = xy + "-" + 1;
        console.log(r);
    }, 200, e)
};

document.getElementById("con").ondblclick = function (e) {
    clearTimeout(clickInterval)
    xy = getXY(e);
    if (xy === null)
        return;
    r = xy + "-" + 3;
    console.log(r);
};