javascript - 如何在 JavaScript 中将两个东西减去......？

Question

我正在制作游戏，我需要扣除适量的积分。我的这个声明不起作用(playerPower)部分。

function checkCol(cell, row){
    var color = map[row][cell];
    console.log(color);
    if (color == "g") {
        alert("Green");
        playerPower -= onGrass - passengerBayPower
    } else if (color == "b") {
        alert("Brown");
        playerPower -= onRock - passengerBayPower
    } else if (color == "w") {
        alert("White");
        playerPower -= onIce - passengerBayPower
    }

-= 和 - 有什么问题吗？

Answer 1

您可以通过以下方式简化它:

var color = map[row][cell];
var diff = 0;
    console.log(color);
    if (color == "g") {
        alert("Green");
        diff = onGrass - passengerBayPower
    } else if (color == "b") {
        alert("Brown");
        diff = onRock - passengerBayPower
    } else if (color == "w") {
        alert("White");
        diff = onIce - passengerBayPower
    }
    playerPower -= diff;