js使用递归函数深拷贝对象
function cloneDeep(source) {
var target = {};
for(var key in source) {
if (Object.prototype.hasOwnProperty.call(source, key)) {
if (typeof source[key] === 'object') {
target[key] = cloneDeep(source[key]);
} else {
target[key] = source[key];
}
}
}
return target;
}