在Objective-C中，如何测试对象类型?

I need to test whether the object is of type NSString or UIImageView. How can I accomplish this? Is there some type of "isoftype" method?

我需要测试对象是否为NSString类型或UIImageView。我怎样才能做到这一点呢?是否存在某种类型的“isoftype”方法?

6 个解决方案

#1

819

If your object is myObject, and you want to test to see if it is an NSString, the code would be:

如果您的对象是myObject，并且您想要测试它是否是一个NSString，那么代码将是:

[myObject isKindOfClass:[NSString class]]

Likewise, if you wanted to test myObject for a UIImageView:

同样，如果您想要为UIImageView测试myObject:

[myObject isKindOfClass:[UIImageView class]]

#2

You would probably use

你可能会用

- (BOOL)isKindOfClass:(Class)aClass

This is a method of NSObject.

这是NSObject的一种方法。

For more info check the NSObject documentation.

有关更多信息，请检查NSObject文档。

This is how you use this.

这就是你如何使用它的方法。

BOOL test = [self isKindOfClass:[SomeClass class]];

You might also try doing somthing like this

你也可以尝试这样做。

for(id element in myArray)
{
    NSLog(@"=======================================");
    NSLog(@"Is of type: %@", [element className]);
    NSLog(@"Is of type NSString?: %@", ([[element className] isMemberOfClass:[NSString class]])? @"Yes" : @"No");
    NSLog(@"Is a kind of NSString: %@", ([[element classForCoder] isSubclassOfClass:[NSString class]])? @"Yes" : @"No");    
}

#3

When you want to differ between a superClass and the inheritedClass you can use:

当您想在超类和继承类之间有所区别时，您可以使用:

if([myTestClass class] == [myInheritedClass class]){
   NSLog(@"I'm the inheritedClass);
} 
if([myTestClass class] == [mySuperClass class]){
   NSLog(@"I'm the superClass);
}

Using - (BOOL)isKindOfClass:(Class)aClass in this case would result in TRUE both times because the inheritedClass is also a kind of the superClass.

使用- (BOOL)isKindOfClass:(类)类的aClass在这一情况下将会是正确的，因为继承类也是一种超类。

#4

Running a simple test, I thought I'd document what works and what doesn't. Often I see people checking to see if the object's class is a member of the other class or is equal to the other class.

运行一个简单的测试，我想我会记录下哪些是可行的，哪些是无效的。我经常看到人们检查对象的类是否是其他类的成员，或者是否等于其他类。

For the line below, we have some poorly formed data that can be an NSArray, an NSDictionary or (null).

对于下面的行，我们有一些很糟糕的数据，可以是NSArray、NSDictionary或(null)。

NSArray *hits = [[[myXML objectForKey: @"Answer"] objectForKey: @"hits"] objectForKey: @"Hit"];

These are the tests that were performed:

这些是进行的测试:

NSLog(@"%@", [hits class]);

if ([hits isMemberOfClass:[NSMutableArray class]]) {
    NSLog(@"%@", [hits class]);
}

if ([hits isMemberOfClass:[NSMutableDictionary class]]) {
    NSLog(@"%@", [hits class]);
}

if ([hits isMemberOfClass:[NSArray class]]) {
    NSLog(@"%@", [hits class]);
}

if ([hits isMemberOfClass:[NSDictionary class]]) {
    NSLog(@"%@", [hits class]);
}

if ([hits isKindOfClass:[NSMutableDictionary class]]) {
    NSLog(@"%@", [hits class]);
}

if ([hits isKindOfClass:[NSDictionary class]]) {
    NSLog(@"%@", [hits class]);
}

if ([hits isKindOfClass:[NSArray class]]) {
    NSLog(@"%@", [hits class]);
}

if ([hits isKindOfClass:[NSMutableArray class]]) {
    NSLog(@"%@", [hits class]);
}

isKindOfClass worked rather well while isMemberOfClass didn't.

isKindOfClass工作得相当好，而isMemberOfClass则没有。

#5

You can make use of the following code incase you want to check the types of primitive data types.

您可以使用下面的代码来检查原始数据类型的类型。

// Returns 0 if the object type is equal to double
strcmp([myNumber objCType], @encode(double))

#6

Simple, [yourobject class] it will return the class name of yourobject.

简单，[yourobject类]它将返回yourobject的类名。

#1

819