json的序列化
// json 序列化的条件: // 1.The top level object is an NSArray or NSDictionary.( 数据的最外层必须是数组或字典 ) // 2.All objects are instances of NSString, NSNumber, NSArray, NSDictionary, or NSNull.(所有对象必须是 NSString, NSNumber, NSArray, NSDictionary, or NSNull类型的对象 ) // 3.All dictionary keys are instances of NSString.(字典中的键必须是NSString类型的对象) // 4.Numbers are not NaN or infinity.(数据中Numbers不能为空或无穷大) 使用json序列化的几种情况: 1. 手动拼接 json NSString *string = @"{\"name\":\"zhangsan\",\"age\":\"26\"}"; NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding]]; 2. 字典 NSDictionary *dict = @{@"name":@"zhangsan",@"age":@"27"};