In the 5.2 version of the ThingSmart SDK, we've introduced a feature to fetch the list of countries. This allows developers to acquire a comprehensive list of countries during login or registration.

Here's how to implement it:

Fetching the Country List

Invoke the following method to successfully fetch the country list:

```objc

[[ThingSmartUser sharedInstance] countryListWithSuccess:^(NSArray<ThingSmartCountryModel *> * _Nonnull list) {

...

} failure:^(NSError *error) {

...

}];

```

In this method, the `success` callback function returns an array of `ThingSmartCountryModel`, where each element represents a country.

ThingSmartCountryModel

This model defines the basic information of a country:

```objc

@interface ThingSmartCountryModel : NSObject

@property (nonatomic, strong) NSString *countryCode;//Country code

@property (nonatomic, strong) NSString *countryAbb;//Country abbreviation

@property (nonatomic, strong) NSString *countryName;//Country name

@property (nonatomic, strong) NSString *firstLetter;//First letter of the country name

@end

```

Implementation for Earlier SDK Versions

For earlier versions of the SDK, you can fetch the country list in the following way:

```objc

[[[TuyaSmartRequest alloc]init] requestWithApiName:@"tuya.m.country.list" postData:nil getData:nil version:@"1.0" success:^(id result) {

NSLog(@"%@",result);

} failure:^(NSError *error) {

}];

```

This method calls back a result, which includes the following fields:

- `p` : Country abbreviation

- `n` : Country name

- `c` : Country code

- `a` : First letter of the country name

Example:

```json

{

"p" : "afghanistan",

"n" : "Afghanistan",

"c" : "93",

"a" : "AF"

}

```