objective-c - NSPredicate 不适用于字典数组

Question

我有一个格式如下的 NSPredication:@"Status CONTAINS[cd] shipped"

我有一个字典数组，下面是一个例子:

{
        {
        Category = "Category 4";
        Comp = "Category 4";
        Depth = 02;
        Grade = New;
        Length = 02;
        Location = "Thousand Oaks, CA";
        Name = "3ply Mat";
        Owner = "Owner 3";
        PUP = 2;
        Status = Shipped;
        "Unit Number" = 20110507113852351;
        Width = 02;
    },
        {
        Category = "Category 4";
        Comp = "Category 4";
        Depth = 02;
        Grade = New;
        Length = 02;
        Location = "Thousand Oaks, CA";
        Name = "3ply Mat";
        Owner = "Owner 3";
        PUP = 2;
        Status = Shipped;
        "Unit Number" = 20110516094641587;
        Width = 02;
    }
)

但它返回一个空数组。我究竟做错了什么？谢谢

Answer 1

你想要:

[NSPredicate predicateWithFormat:@"Status =[cd] 'shipped'"];

或者:

[NSPredicate predicateWithFormat:@"Status =[cd] %@", @"shipped"];

你的问题是你的谓词格式已经shipped，而它应该已经'shipped'。缺少单引号意味着它试图将 [dictionary valueForKey:@"Status"] 与 [dictionary valueForKey:@"shipped"] 进行比较，而不是与字符串进行比较文字 @"shipped".