filteredArrayUsingPredicate不过滤数据

Question

我正在开发iOS应用程序，其中我有searchBar。

我想要的是，

当用户在searchBar中输入s时，我希望从我的数组中获得以Merchant_Name开头的所有s

这是我尝试过的代码片段，但它无效，

我的arr包含：

 arr at index 0 = {
        "Merchant_Id" = 1261;
        "Merchant_Name" = "Magazine Mall";
        "Merchant_Url" = "magazine-mall";
    },
     arr at index 1 =   {
        "Merchant_Id" = 1262;
        "Merchant_Name" = MakeMyTrip;
        "Merchant_Url" = makemytrip;
    },
   arr at index 2 =     {
        "Merchant_Id" = 1263;
        "Merchant_Name" = Travelguru;
        "Merchant_Url" = travelguru;
    },
    arr at index 3 =    {
        "Merchant_Id" = 1266;
        "Merchant_Name" = Travelchacha;
        "Merchant_Url" = travelchacha;
    },
      arr at index 4 =  {
        "Merchant_Id" = 1267;
        "Merchant_Name" = Tradus;
        "Merchant_Url" = tradus;
    },
    arr at index 5 =    {
        "Merchant_Id" = 1268;
        "Merchant_Name" = ToyWorld;
        "Merchant_Url" = toyworld;
    },
     arr at index 6 =   {
        "Merchant_Id" = 1269;
        "Merchant_Name" = Topskin;
        "Merchant_Url" = topskin;
    },
   ....

代码：

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"Merchant_Name LIKE[cd] %@ ",searchText];
NSMutableArray *filter1 =[[NSMutableArray alloc] init];
filter1 = [[arr filteredArrayUsingPredicate:predicate] mutableCopy];
NSLog(@"predicate  = %@ -------  filter=%@",predicate,filter1);

日志显示：

predicate  = Merchant_Name LIKE[cd] "s" -------  filter=(
)

请帮助我，我在哪里做错了？

提前致谢。

Answer 1

NSPredicate *predicate =[NSPredicate predicateWithFormat:@"name beginswith[c] %@", searchText];

NSMutableArray *filter1 =[[NSMutableArray alloc] init];
filter1 = [[arr filteredArrayUsingPredicate:predicate] mutableCopy];
NSLog(@"predicate  = %@ -------  filter=%@",predicate,filter1);

更多了解遵循此

https://developer.apple.com/library/mac/documentation/cocoa/conceptual/predicates/Articles/pUsing.html

Answer 2

为BeginsWith更改你的LIKE

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"Merchant_Name beginswith[c] %@ ",searchText];
NSMutableArray *filter1 =[[NSMutableArray alloc] init];
filter1 = [[arr filteredArrayUsingPredicate:predicate] mutableCopy];
NSLog(@"predicate  = %@ -------  filter=%@",predicate,filter1);

Answer 3

[NSPredicate predicateWithFormat:@"Merchant_Name beginswith %@", [searchText uppercaseString]];