Question

我有一个像这样的Object类

@interface Recipe : NSObject
@property (nonatomic, strong) NSString *name; // name of recipe
@property (nonatomic, strong) NSString *prepTime; // preparation time
@end

Normaly，我通过这种方式添加新对象。

Recipe *myClass = [Recipe new];
myClass.name = @"This is name";
myClass.prepTime = @"This is time";

Recipe *myClass1 = [Recipe new];
myClass1.name = @"This is name1";
myClass1.prepTime = @"This is time1";

Recipe *myClass2 = [Recipe new];
myClass2.name = @"This is name2";
myClass2.prepTime = @"This is time2";

现在，我有一个来自数组的字典，我想将字典中的所有值都添加到for循环中的对象中。

NSMutableArray *recipes;
NSArray *somoData = [self downloadSoMo];
for (NSDictionary *dict in someData)
{
    Recipe *myClass = [Recipe new];
    myClass.name = [dict objectForKey:@"DreamName"];
    myClass.prepTime = [dict objectForKey:@"Number"];
    [recipes addObject:myClass];
}

上面的代码无法正常工作，我不知道为什么，请帮我解决一下

Answer 1

您需要分配食谱例如 NSMutableArray * recipes = [[NSMutableArray alloc] init];

NSMutableArray *recipes = [[NSMutableArray alloc] init];
NSArray *somoData = [self downloadSoMo];
for (NSDictionary *dict in someData)
{
    Recipe *myClass = [Recipe new];
    myClass.name = [dict objectForKey:@"DreamName"];
    myClass.prepTime = [dict objectForKey:@"Number"];
    [recipes addObject:myClass];
}

Answer 2

我建议你在Recipe类中创建一个方法来创建它的实例。

像这样，

在Recipe.h

- (instancetype) initRecipeWithDictionary:(NSDictionary *)dicRecipe;

在Recipe.m

- (instancetype) initRecipeWithDictionary:(NSDictionary *)dicRecipe {
    self = [super init];
    if(self) {
       self.name = [dicRecipe objectForKey:@"DreamName"];
       self.prepTime = [dicRecipe objectForKey:@"Number"];
    }
    return self;
}

现在您可以像这样使用它：

NSMutableArray *recipes = [[NSMutableArray alloc] init];
NSArray *somoData = [self downloadSoMo];
for (NSDictionary *dict in someData)
{
    Recipe *myClass = [[Recipe alloc] initRecipeWithDictionary:dict];
    [recipes addObject:myClass];
}

通过这种方式，您的初始化逻辑将被编写在一个地方，如果您想要更改某些内容，通过更改单个文件Recipe将很容易处理它。

xcode Objective C从nsdictionary添加对象项

2 个答案: