含nsdictionary的nsmutablearray中删除重

含nsdictionary的nsmutablearray中删除重

本文介绍了从包含nsdictionary的nsmutablearray中删除重复项的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

我想从nsmutablearray中删除重复项。

I want to remove duplicates from nsmutablearray.

数组结构: -

(
    {
        "act_end_date" = "";
        "act_entry_date" = "13/11/2014";
        "act_recurrrance_type" = Daily;
        "act_start_date" = "2014-11-13";
        "row_id" = 0;
        "act_id" = 2;
    }
    {
        "act_end_date" = "";
        "act_entry_date" = "13/11/2014";
        "act_recurrrance_type" = Daily;
        "act_start_date" = "2014-11-13";
        "row_id" = 1;
        "act_id" = 2;
    }
    {
        "act_end_date" = "";
        "act_entry_date" = "16/11/2014";
        "act_recurrrance_type" = Daily1;
        "act_start_date" = "2014-11-15";
        "row_id" = 2;
        "act_id" = 3;
    }
)


我想要的是检查数组包含任何字典whi的位置ch有相同的act_id。
如果是,则删除第一个字典。
即上述数组的预期结果: -

What I want is to check where array contain any dictionary which have same act_id.If yes then remove 1st dictionary.i.e the expected result for the above arrayis :-

(
        {
            "act_end_date" = "";
            "act_entry_date" = "13/11/2014";
            "act_recurrrance_type" = Daily;
            "act_start_date" = "2014-11-13";
            "row_id" = 1;
            "act_id" = 2;
        }
        {
            "act_end_date" = "";
            "act_entry_date" = "16/11/2014";
            "act_recurrrance_type" = Daily1;
            "act_start_date" = "2014-11-15";
            "row_id" = 2;
            "act_id" = 3;
        }
    )

他们有什么办法吗?
可以使用NSPREDICATE吗?

Is their any way?Is it possible by using NSPREDICATE?

我试图用以下方式做到: -

I Tries to do it in below way :-

  NSMutableArray *filteredArray = [NSMutableArray array];

    for (NSMutableDictionary* E1 in Event_Array)
    {

        BOOL hasDuplicate = [[filteredArray filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"act_id == %@", [E1 objectForKey:@"act_id"]]] count] > 0;

        if (!hasDuplicate)
        {
            [filteredArray addObject:E1];
        }
    }

因为它返回数组:---

For it returns array :---

(
    {
        "act_end_date" = "";
        "act_entry_date" = "13/11/2014";
        "act_recurrrance_type" = Daily;
        "act_start_date" = "2014-11-13";
        "row_id" = 0;
        "act_id" = 2;
    }
)

我想要的是

(
    {
        "act_end_date" = "";
        "act_entry_date" = "13/11/2014";
        "act_recurrrance_type" = Daily;
        "act_start_date" = "2014-11-13";
        "row_id" = 1;
        "act_id" = 2;
    }
)


推荐答案

假设你想要最新的对象将在列表中。

Assuming you want the latest object to be in the list.

解决方案1:(简单)

反转你的数组

NSMutableArray *filteredArray = [NSMutableArray array];
for (int i = Event_Array.count-1; i>= 0; i--)
{
    NSMutableDictionary* E1 = [Event_Array objectAtIndex:i];
    BOOL hasDuplicate = [[filteredArray filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"act_id == %@", [E1 objectForKey:@"act_id"]]] count] > 0;

    if (!hasDuplicate)
    {
        [filteredArray addObject:E1];
    }
}

解决方案2:

使用NSMutableDictionary而不是数组。

Use NSMutableDictionary instead of array.

//Keys are act_id(s)
"2" = {
    "act_end_date" = "";
    "act_entry_date" = "13/11/2014";
    "act_recurrrance_type" = Daily;
    "act_start_date" = "2014-11-13";
    "row_id" = 1;
    "act_id" = 2;
};
"3" = {
    "act_end_date" = "";
    "act_entry_date" = "16/11/2014";
    "act_recurrrance_type" = Daily1;
    "act_start_date" = "2014-11-15";
    "row_id" = 2;
    "act_id" = 3;
}


这篇关于从包含nsdictionary的nsmutablearray中删除重复项的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!

08-14 12:04