NSMutableArray动态更新？

Question

我有如下代码。

Ticket *ticket1 = [[Ticket alloc] initWithName:@"INC1234" group:@"PIMS-EU-COG" type:@"Incident" status:@"Active" createdOn:@"20-Oct-2013" createdBy:@"Dinesh" completionDate:@"23-Oct-2013" notes:@"1. All works coreectly 2. New variables are created.."];
Ticket *ticket2 = [[Ticket alloc] initWithName:@"PRJ2342" group:@"PIMS-EU-COG" type:@"Project" status:@"Closed" createdOn:@"20-Oct-2013" createdBy:@"Dinesh" completionDate:@"23-Oct-2013" notes:@"1. All works coreectly 2. New variables are created.."];
Ticket *ticket3 = [[Ticket alloc] initWithName:@"ENC1234" group:@"PIMS-EU-COG" type:@"Enhancement" status:@"Awaiting vendor" createdOn:@"20-Oct-2013" createdBy:@"Dinesh" completionDate:@"23-Oct-2013" notes:@"1. All works coreectly 2. New variables are created.."];
Ticket *ticket4 = [[Ticket alloc] initWithName:@"INC2345" group:@"CRM-EU-COG" type:@"Incident" status:@"Active" createdOn:@"20-Oct-2013" createdBy:@"Alex" completionDate:@"23-Oct-2013" notes:@"1. All works coreectly 2. New variables are created.."];
Ticket *ticket5 = [[Ticket alloc] initWithName:@"PRJ2345" group:@"CRM-EU-COG" type:@"Project" status:@"Pending" createdOn:@"20-Oct-2013" createdBy:@"Alex" completionDate:@"23-Oct-2013" notes:@"1. All works coreectly 2. New variables are created.."];
Ticket *ticket6 = [[Ticket alloc] initWithName:@"ENC2345"group:@"CRM-EU-COG" type:@"Enhancement" status:@"Active" createdOn:@"20-Oct-2013" createdBy:@"Alex" completionDate:@"23-Oct-2013" notes:@"1. All works coreectly 2. New variables are created.."];

self.TicketsFinal= [NSMutableArray arrayWithObjects:ticket1,ticket2,ticket3, nil];
/*
if (groupFinal == @"PIMS-EU-COG") {

    self.TicketsFinal= [NSMutableArray arrayWithObjects:ticket1,ticket2,ticket3, nil];
}else if (groupFinal == @"CRM-EU-COG")
{
    self.TicketsFinal= [NSMutableArray arrayWithObjects:ticket4,ticket5,ticket6,ticket7,ticket8,ticket9, nil];
}*/

我有三个参数：

1. GroupFinal
2. TypeFinal
3. StatusFinal。

groupsFinal将持有该小组(如:PIMS COG)的详细信息.typeFinal将持有何种类型的票证(例如:意外)，而statusFinal将保存票证的状态(ex: Active)。这3个参数是从先前的观点得到的。

我有一个名为self.ticketsFinal的数组，它应该仅根据所选的标准来保存票证。我尝试了硬编码组(最后评论部分)和导航，这不是正确的方法。

例:当groupFinal、TypeFinal、statusFinal的值为PIMS-EU-COG、Incident、Active时，在这种情况下，self.TiketsFinal应该只包含Ticket1 (这符合标准)。

当All在typeFinal和statusFinal中被选中时，组中的所有票证都应该在数组中更新。

有人能帮忙吗。你的帮助非常感谢。

Answer 1

为此，您可能可以使用NSPredicate：

[self.TicketsFinal filteredArrayUsingPredicate:
    [NSPredicate predicateWithFormat:@"group = %@", @"PIMS-EU-COG"]];

这将返回一个新数组，该数组只包含组等于“PIMS”的对象。

您可以看到使用NSPredicate 这里的指南。

而且，如果使用此方法，则数组不需要是可变的。如果您确实希望丢弃与不匹配的项，则可以这样做

[self.TicketsFinal filterUsingPredicate:
    [NSPredicate predicateWithFormat:@"group = %@", @"PIMS-EU-COG"]];

在这种情况下，需要使用多个参数来筛选对象集。您可以为此使用NSCompoundPredicate：

NSPredicate *groupPredicate = [NSPredicate 
     predicateWithFormat:@"group = %@", @"PIMS-EU-COG"];

NSPredicate *typePredicate = [NSPredicate 
     predicateWithFormat:@"type = %@", @"Incident"];

NSCompoundPredicate *compoundPredicate = [NSCompoundPredicate 
     andPredicateWithSubpredicates:@[groupPredicate, typePredicate]];

NSArray *result = [self.TicketsFinal filteredArrayUsingPredicate:compoundPredicate];