javascript - 我们可以在 JavaScript 函数中通过引用传递变量吗？

Question

我正在通过 javascript 函数计算给定点的行和列。
为了实现这一点，我必须声明全局变量

var global_row;
var global_col;

这是函数体

function calculate_city_row_col(cur_city_id)
{
    var r = 565;
    var c = 1;
    var max_city_id = 159895;
    do{
        if((r%2) == 0) c++;
        max_city_id -= r;
        r--;
    }
    while(cur_city_id <= max_city_id)

    //Saving Result in seperate row and column
    global_row = r + 1;                                 //Global Variable
    global_col = c + (cur_city_id - (max_city_id + 1)); //Global Variable
}

这里是函数调用

var city_id = 1244;
calculate_city_row_col(city_id);
var city_row = global_row;
var city_col = global_col;

有没有办法直接传递局部变量？ (不使用全局变量)
像这样

calculate_city_row_col(cur_city_id, city_row_ref, city_col_ref);

Answer 1

只返回一个对象:

function calculate_city_row_col(cur_city_id)
{
    var r = 565;
    var c = 1;
    var max_city_id = 159895;
    do{
        if((r%2) == 0) c++;
        max_city_id -= r;
        r--;
    }
    while(cur_city_id <= max_city_id)

    return {
        row: r + 1,
        col: c + (cur_city_id - (max_city_id + 1))
    };
}

var rowAndCol = calculate_city_row_col(1244);
var city_row = rowAndCol.row;
var city_col = rowAndCol.col;