我如何检查NSArray中是否存在特定的NSString？

How might I check if a particular NSString is presnet in an NSArray?

我如何检查特定的NSString是否是NSArray中的presnet？

3 个解决方案

#1

You can do it like,

你可以这样做，

NSArray* yourArray = [NSArray arrayWithObjects: @"Str1", @"Str2", @"Str3", nil];
if ( [yourArray containsObject: yourStringToFind] ) {
    // do found
} else {
    // do not found
}

#2

Iterating or containsObject are order n ways to find.

Iterating或containsObject是n种查找方式。

If you want constant time lookup, you can also maintain a hash table like NSSet or NSHashTable but that increases space but saves time.

如果您想要恒定时间查找，您还可以维护一个像NSSet或NSHashTable这样的哈希表，但这会增加空间但节省时间。

NSArray* strings = [NSArray arrayWithObjects: @"one", @"two", @"three", nil];
NSSet *set = [NSSet setWithArray:strings];

NSString* stringToFind = @"two";
NSLog(@"array contains: %d", (int)[strings containsObject:stringToFind]);
NSLog(@"set contains: %d", (int)[set containsObject:stringToFind]);   

#3

Depends on your needs. Either indexOfObject if you care about equality (most likely), or indexOfObjectIdenticalTo if you care it's actually the same object (i.e. same address).

取决于您的需求。如果你关心相等（最有可能），可以使用indexOfObject，或者如果你关心它就是indexOfObjectIdenticalTo它实际上是同一个对象（即相同的地址）。

Source:

资源：

• NSArray Class Reference
• NSArray类参考