Question

我有一个NSArray与NSMutableDictionaries。示例testArray =[dict1,dict2,dict3,dict4]. 数组中的每个字典都类似于

dict1=  {
    country = "INDIA";
    flag = "A";
    Currency = "Rupees";
    rate = 10;
}

所有值都可以更改。有时候

dict1 = {
    country = "USA";
    flag = "SA";
    Currency = "Dollar";
    rate = 50;
   }

如果country = "INDIA"和flag = "A"以及Currency = "Rupees"并且不需要更改费率键的值，我需要更新testArray中所有词典的关键费率值testArray旁边的其他词典。

Answer 1

试试下面的内容。

for(NSMutableDictionary *dic in array)
{
    if([[dic valueForKey:@"country"] isEqualToString:@"INDIA"] &&
       [[dic valueForKey:@"flag"] isEqualToString:@"A"] &&
       [[dic valueForKey:@"Currency"] isEqualToString:@"Rupees"])
    {
        [dic setValue:@"100" forKey:@"rate"];
    }
}

Answer 2

以下是您需要的完整示例

NSDictionary *dict1 =  @{
                             @"country" : @"INDIA",
                             @"flag" : @"A",
                             @"Currency" : @"Rupees",
                             @"rate" : @10
                             };
    NSDictionary *dict2 = @{
                            @"country" : @"USA",
                            @"flag" : @"SA",
                            @"Currency" : @"Dollar",
                            @"rate" : @50
                            };
    NSArray *testArray = @[dict1, dict2];
    NSMutableArray *testMutableArray = [testArray mutableCopy];
    for (int i = 0; i < testMutableArray.count; i++) {
        NSDictionary *country = testMutableArray[i];
        if ([country[@"country"] isEqualToString:@"INDIA"] &&
            [country[@"flag"] isEqualToString:@"A"] &&
            [country[@"Currency"] isEqualToString:@"Rupees"])
        {
            NSMutableDictionary *countryMutable = [country mutableCopy];
            countryMutable[@"rate"] = @100;
            testMutableArray[i] = [countryMutable copy];
        }
    }
    testArray = [testMutableArray copy];

Answer 3

使用NSMutableArray而不是NSArray。

然后，

NSDictionary *dict = [testArray objectAtIndex:0];

dict[@"rate"] = @"11";

[testArray replaceObjectAtIndex:0 withObject:dict];

希望这会对你有所帮助。

如何根据另一个键值对替换NSMutableDictionary中键的值

3 个答案: