assign 的深拷贝

类别：js / 日期：2022-11-22 / 浏览：519 / 评论：0

function clone(obj) {
    var copy;
    switch (typeof obj) {
        case "undefined": break;
        case "number": copy = obj - 0;
            break;
        case "string": copy = obj + "";
            break;
        case "boolean": copy = obj;
            break;
        case "object": //object 分为两种情况 对象（Object）和数组（Array） 
            if (obj === null) {
                copy = null;
            } else {
                if (Object.prototype.toString.call(obj).slice(8, -1) === "Array") {
                    copy = []; for (var i = 0; i < obj.length; i++) {
                        copy.push(clone(obj[i]));
                    }
                } else {
                    copy = {}; for (var j in obj) {
                        copy[j] = clone(obj[j]);
                    }
                }
            }
            break; default: copy = obj; break;
    }
    return copy;
}