將Json存進本地資料夾 NSArray *paths=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *path=[paths objectAtIndex:0];
    NSString *Json_path=[path stringByAppendingPathComponent:@"JsonFile.json"];
    //==寫入檔案
    NSLog(@"%@",[JsonData writeToFile:Json_path atomically:YES] ? @"Succeed":@"Failed"); ----------------------- 讀取Json //==Json檔案路徑
    NSArray *paths=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *path=[paths objectAtIndex:0];
    NSString *Json_path=[path stringByAppendingPathComponent:@"JsonFile.json"];
    //==Json資料
    NSData *data=[NSData dataWithContentsOfFile:Json_path];
    //==JsonObject
 id JsonObject=[NSJSONSerialization JSONObjectWithData:data
 options:NSJSONReadingAllowFragments
 error:&error]   //nslog (@"%@",jsonobject);列印json字典