js深度复制

//深度优先复制
function deepClone(obj){    //可深度复制所有原始类型、数组、Object对象、函数、Date、
  if(obj instanceof Object){
    let new_obj = null;
    switch(obj.constructor){
        case Array:
            new_obj = [];
            for (let key of Object.keys(obj)){
              new_obj[key] = deepClone(obj[key]);
            }
            break;
        case Object:
            new_obj = {};
            for (let key of Object.keys(obj)){
              new_obj[key] = deepClone(obj[key]);
            }
            break;
        case Function:
            new_obj = eval('(' + obj.toString() + ')');
            break;
        case Date:
            new_obj = new Date(obj.getTime());
            break;
        default :
            new_obj = obj;
    }
    return new_obj;
  }else {
    return obj;
  }
}