1. Objc_xxx series of functions

The objC_ family of functions focuses on macro usage, such as class and protocol space allocation, registration, logout, and other operations

• objc_getClassGet the Class object
• objc_getMetaClassGet the MetaClass object
• objc_allocateClassPairAllocate space, create classes (member variables can be added only after creation, but before registration)
• objc_registerClassPairRegister a class (you can use that class to create objects)
• objc_disposeClassPairUnregister a class
• objc_allocateProtocolOpen up space to create protocols
• objc_registerProtocolRegister a protocol
• objc_constructInstanceConstruct an instance object (invalid under ARC)
• objc_destructInstanceDestruct an instance object (invalid under ARC)
• objc_setAssociatedObjectAssociate an object with an instance object
• objc_getAssociatedObje*ctGets the associated object of the instance object
• objc_removeAssociatedObjectsClears all associated objects of the instance object

2. Class_xxx series functions

The class_ family of functions focuses on the internals of a class, such as instance variables, attributes, methods, protocols, etc

• class_addIvarAdd instance variables for the class
• class_addPropertyAdd attributes to the class
• class_addMethodAdd methods for classes
• class_addProtocolFollow the protocol for the class
• class_replaceMethodReplace the implementation of a method of a class
• class_getNameGet the name of the class
• class_isMetaClassDetermine whether it is a metaclass
• objc_getProtocolGet a protocol
• objc_copyProtocolListCopy the list of protocols registered at run time
• class_getSuperclassGets the parent of a class
• class_setSuperclassSets the parent of a class
• class_getPropertyGets a property of a class
• class_getInstanceVariableGet instance variables
• class_getClassVariableGet class variables
• class_getInstanceMethodGet instance method
• class_getClassMethodGet class methods
• class_getMethodImplementationGet the implementation of the method
• class_getInstanceSizeGets the size of an instance of the class
• class_respondsToSelectorDetermines whether a class implements a method
• class_conformsToProtocolDetermines whether a class complies with a protocol
• class_createInstanceCreate an instance of the class
• class_copyIvarListCopy the list of instance variables of the class
• class_copyMethodListCopy the list of methods for the class
• class_copyProtocolListCopy the list of protocols that the class follows
• class_copyPropertyListCopy the property list of the class

3.object_xxx series of functions

The objcet_ family of functions focuses on object perspectives, such as instance variables

• object_copyObject copy(ARC invalid)
• object_disposeObject release (ARC invalid)
• object_getClassNameGets the class name of the object
• object_getClassGets the Class of the object
• object_setClassSets the Class of the object
• object_getIvarGets the value of an instance variable in an object
• object_setIvarSets the value of the instance variable in the object
• object_getInstanceVariableGet the value of the instance variable in the object (not valid in ARC, using object_getIvar)
• object_setInstanceVariableSet the value of an instance variable in an object (not valid in ARC, using object_setIvar)

4. Method_xxx series of functions

The method_ family of functions focuses on the inside of a method, the parameters and return value types of the method, and the implementation of the method

• method_getNameGet method name
• method_getImplementationGet the implementation of the method
• method_getTypeEncodingGets the type encoding of the method
• method_getNumberOfArgumentsGets the number of arguments to the method
• method_copyReturnTypeThe return type of the copy method
• method_getReturnTypeGets the return type of the method
• method_copyArgumentTypeThe parameter type of the copy method
• method_getArgumentTypeGets the parameter type of the method
• method_getDescriptionGets a description of the method
• method_setImplementationThe implementation of the set method
• method_exchangeImplementationsImplementation of replacement methods

5. Property_xxx series functions

Property_ class functions look inside properties, such as properties of properties

• property_getNameGet attribute name
• property_getAttributesGets the property list for the property
• property_copyAttributeListProperty list of copy properties
• property_copyAttributeValueCopies the value of a property in the property

6. Protocol_xxx series functions

• protocol_conformsToProtocolDetermine whether one protocol complies with another
• protocol_isEqualDetermine whether the two protocols are consistent
• protocol_getNameObtaining the protocol name
• protocol_copyPropertyListCopy the protocol property list
• protocol_copyProtocolListCopy the protocol list followed by a protocol
• protocol_copyMethodDescriptionListList of methods to copy the protocol
• protocol_addProtocolFollow one protocol for another
• protocol_addPropertyAdd attributes for the protocol
• protocol_getPropertyGets an attribute in the protocol
• protocol_addMethodDescriptionAdd a method description for the protocol
• protocol_getMethodDescriptionGets the description of a method in the protocol

Ivar_xxx series of functions

• ivar_getNameObtain the Ivar name
• ivar_getTypeEncodingGet type encoding
• ivar_getOffsetGet offset

Sel_xxx series of functions

• sel_getNameGet the name
• sel_getUidRegistration method
• sel_registerNameRegistration method
• sel_isEqualDetermine whether the methods are equal

9. Imp_xxx series functions

• imp_implementationWithBlockCreate imPs from blocks of code
• imp_getBlockGets a block of code in a function pointer
• imp_removeBlockRemove code blocks in IMP