Question

我是iOS新手，

我有一个NSdictionary的NSMutableArray，

我想要做所有相同键的总和，这是我尝试但没有成功的代码

ARQProfileDataArray（这是NSMutableArray）：

{
"type":"arqEquity",
"category":"Equity",
"investment":"6935.7",
"percentage":"25.43"
},
{
"type":"liquid",
"category":"MF",
"investment":0,
"percentage":0
},
{
"type":"balanced",
"category":"MF",
"investment":"10215.87",
"percentage":"37.46"
},
{
"type":"equityMF",
"category":"MF",
"investment":"10123.41",
"percentage":"37.12"
}

我希望将所有category加上MF以及所有category加上Equity

的总和

我的代码：

 NSNumber *sum = [ARQProfileDataArray valueForKeyPath:@"@sum.category"];
  NSLog(@"sum---------- %@",sum);

我的代码在此行NSNumber *sum = [ARQProfileDataArray valueForKeyPath:@"@sum.category"];

上崩溃了

请帮助我犯错的地方？提前致谢!!

Answer 1

使您的NSMutableArray循环。请检查Objective-C的语法及其长时间和时间。我没有检查过

screen -r tensroboard-screen

现在您在//Declare variable for category types int mfCount = 0 int equityCount = 0 for dict in ARQProfileDataArray { if ([dict[@"category"] isEqualToString:@"MF"]) { mfCount += 1; } else if ([dict[@"category"] isEqualToString:@"Equity"]) { equityCount += 1; } }中有一些类别。

如果您不想为每个键创建变量，那么您可以改为使用字典而不是在案件内部更新。

Answer 2

请找一个简单而通用的解决方案。

    NSMutableArray *sumArray = [@[@{
        @"type":@"arqEquity",
        @"category":@"Equity",
        @"investment":@6935.7,
        @"percentage":@"25.43"
    },
    @{
        @"type":@"liquid",
        @"category":@"MF",
        @"investment":@0,
        @"percentage":@0
    },
    @{
        @"type":@"balanced",
        @"category":@"MF",
        @"investment":@10215.87,
        @"percentage":@"37.46"
    },
    @{
        @"type":@"equityMF",
        @"category":@"MF",
        @"investment":@10123.41,
        @"percentage":@"37.12"
        }] mutableCopy];

    // It will work for Number and Integer.
    NSNumber *sum = [sumArray valueForKeyPath:@"@sum.investment"];
    NSLog(@"Sum of Investment : %@", sum);

    NSArray *categorys = [sumArray valueForKeyPath:@"@distinctUnionOfObjects.category"];
    for (NSString* item in categorys)
    {

        NSArray *categoryArray = [self findSameValueKey:sumArray WithKey:@"category" WithValue:item];
        NSLog(@"%@ count: %@", item,@([categoryArray count]));
    }


    // Helps to find same value key.
    -(NSArray*)findSameValueKey:(NSArray*)dateArray WithKey:(NSString*)key WithValue:(NSString*)value{
        NSPredicate *predicate = [NSPredicate predicateWithBlock:^BOOL(NSDictionary *resultsDictionary, NSDictionary *bind){
            if ([resultsDictionary objectForKey: key] && [[resultsDictionary objectForKey: key] isEqualToString:value]) {
                return true;
            }
            return false;
        }];

        // Apply the predicate block .
        NSArray *sameValueKeys = [dateArray filteredArrayUsingPredicate:predicate];
        return sameValueKeys;
    }

所有相同键的总和iOS

2 个答案: