NSUserDefaults适合存储轻量级的本地数据，主要用于保存用户名、密码等常用资料。
主要保存数据类型：NSString、BOOL、NSInteger、Float、Double、NSArray、NSDictionary
保存数据
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
//保存字符串
[userDefaults setObject:@"张三" forKey:@"name"];
//保存整型
[userDefaults setInteger:26 forKey:@"age"];
//保存BOOL类型
BOOL result = YES;
[userDefaults setBool:result forKey:@"true"];
//保存数组
NSArray *array1 = @[@"张三",@"李四",@"王五"];
[userDefaults setObject:array1 forKey:@"array1"];
//保存字典
NSDictionary *dict1 = @{@"name":@"张三",@"age":@"26",@"job":@"工程师"};
[userDefaults setObject:dict1 forKey:@"dict1"];
//强制储存
[userDefaults synchronize];
读取数据
NSUserDefaults *userDefault = [NSUserDefaults standardUserDefaults];
读取字符串
NSString *name = [userDefault objectForKey:@"name"];
读取整型
NSInteger age = [userDefault integerForKey:@"age"];
读取BOOL
BOOL result = [userDefault boolForKey:@"true"];
读取数组
NSArray *array1 = [userDefault objectForKey:@"array1"];
读取字典
NSDictionary *dict = [userDefault objectForKey:@"dict1"];
