使用相同的键合并NSMutableArray中的对象数据

Ryasoh 发表于 Dev

良寿

我有以下NSMutableArray，其键为“ id，value，name”和“ id，animal”：

    <__NSArrayM 0x7a64f450>(
    {
        id = ccc;
        value = 11;
        name = "Greg";
    },
    {
        id = bbb;
        value = 2;
        name = "Dan";
    },
    {
        id = aaa;
        value = 23;
        name = "Mary";
    },
    {
        id = aaa;
        animal = "dog";
    },
    {
        id = ccc;
        animal = "cat";
    }

)

是否可以通过匹配键来合并内容？所以最后我会得到：

        <__NSArrayM 0x7a64f450>(
        {
            id = ccc;
            value = 11;
            name = "Greg";
            animal = "cat"
        },
        {
            id = bbb;
            value = 2;
            name = "Dan";
        },
        {
            id = aaa;
            value = 23;
            name = "Mary";
            animal = "dog";
        }

    )

我正在寻找如果键匹配id的对象组合。所有其他键应合并在一起。

甘道夫

一个更优雅的方法是使用NSPredicate。使用此代码。arrRecords是您在合并之前存储所有记录的位置。

NSString *strKey;  
NSPredicate *predicate;  
NSArray *tempArray;       

for(int i = 0; i < [arrRecords count]; i++) {
    strKey = [[arrRecords objectAtIndex:i] valueForKey:@"id"];
    predicate = [NSPredicate predicateWithFormat:@"id == %@",strKey];
    tempArray = [arrRecords filteredArrayUsingPredicate:predicate];
    if([tempArray count] > 1) {
       for(int j =0; j < [tempArray count]-1; j++) {
       [[arrRecords objectAtIndex:i] addEntriesFromDictionary:[tempArray objectAtIndex:j+1]];
       [arrRecords removeObject:[tempArray objectAtIndex:j+1]];  // You need to remove the record from super set otherwise this will get duplicated again.
            }
        }
    }

编辑-NSDictionary对象的代码

NSMutableArray *newRecords = [[NSMutableArray alloc] init]; // Add this also before method body

 for(int i = 0; i < [arrRecords count]; i++) {  

     strKey = [[arrRecords objectAtIndex:i] valueForKey:@"id"];  
     predicate = [NSPredicate predicateWithFormat:@"id == %@",strKey];  
     tempArray = [arrRecords filteredArrayUsingPredicate:predicate];  
     if([tempArray count] > 1) {  
         NSMutableDictionary *tempDict = [[NSMutableDictionary alloc] init];   
         for(int j =0; j < [tempArray count]; j++) {  
             [tempDict addEntriesFromDictionary:[tempArray objectAtIndex:j]];  
             if(j!=0) {  
                [arrRecords removeObject:[tempArray objectAtIndex:j]];  
             }                
         }  
         [newRecords addObject:tempDict];
     }
     else {
        [newRecords addObject:[arrRecords objectAtIndex:i]];
     }  
 }