javascript - 无法删除事件监听器

Question

我在所选函数内创建了事件监听器，但无法在“win”函数中将其删除。 (choose函数是在setInterval中实现的，但只有在调用clearInterval之后才实现) 我怎样才能删除这个事件监听器？我不希望点击后文本可以更改。

function chose() {
    canvas.onmousemove = function (event) {
        if (((ballPos == 1) & (event.clientX > posX1) & (event.clientX < posX1 + cupw) & (event.clientY > posY) & (event.clientY < posY + cuph)) |
            ((ballPos == 2) & (event.clientX > posX2) & (event.clientX < posX2 + cupw) & (event.clientY > posY) & (event.clientY < posY + cuph)) |
            ((ballPos == 3) & (event.clientX > posX3) & (event.clientX < posX3 + cupw) & (event.clientY > posY) & (event.clientY < posY + cuph)))
            win = true;

        else
            win = false;
        canvas.addEventListener('click', function () {
            winpage(win);
        }, false);
    }

}

function winpage(win) {
    canvas.removeEventListener('click', function () {
        winpage(win);
    }, false);
    context.clearRect(0, 0, w, h);
    context.drawImage(backGround, 0, 0, w, h);
    if (win)
        context.fillText("YOU WIN!!!", w / 2, h / 2);
    else
        context.fillText("YOU LOSE!!!", w / 2, h / 2);
}

Answer 1

它必须是完全相同的函数。

var handler = function () {
        winpage(win);
    };
function chose() {
    canvas.onmousemove = function (event) {
        if (((ballPos == 1) & (event.clientX > posX1) & (event.clientX < posX1 + cupw) & (event.clientY > posY) & (event.clientY < posY + cuph)) |
            ((ballPos == 2) & (event.clientX > posX2) & (event.clientX < posX2 + cupw) & (event.clientY > posY) & (event.clientY < posY + cuph)) |
            ((ballPos == 3) & (event.clientX > posX3) & (event.clientX < posX3 + cupw) & (event.clientY > posY) & (event.clientY < posY + cuph)))
            win = true;

        else
            win = false;
        canvas.addEventListener('click', handler, false);
    }

}

function winpage(win) {
    canvas.removeEventListener('click', handler, false);
    context.clearRect(0, 0, w, h);
    context.drawImage(backGround, 0, 0, w, h);
    if (win)
        context.fillText("YOU WIN!!!", w / 2, h / 2);
    else
        context.fillText("YOU LOSE!!!", w / 2, h / 2);
}