Obtaining a list of properties for a class through the OC Runtime (runtime)

In the recent period of time in the study of OC's run-time mechanism, encountered a called property_getattributes function, and then the use of a simple summary.

Property_getattributes is primarily used to obtain property data for a class, also known as metadata (metadata), which involves run-time functions including class_copypropertylist, Property_getname and Propert_getattributes

The general usage is as follows:

#import <objc/runtime.h>......-(void) custom{unsigned pcount;        objc_property_t *properties=class_copypropertylist ([self class], &pcount);//property array for (int i=0;i<pcount;++i) {        objc_property_t Property=properties[i];        NSLog (@ "propertyname:%s", Property_getname (property));    NSLog (@ "propertyattributes:%s", property_getattributes (property)); }}

The specific usage is as follows:

eg. defines a class Customclass, with attributes defined as follows

Header file:

Customclass.h#import <objc/runtime.h> @property (nonatomic, strong) NSString *myname;

Implementation file:

Customclass.m@synthesize myname;-(void) printallattributes{unsigned pcount;        objc_property_t *properties=class_copypropertylist ([self class], &pcount);//property array for (int i=0;i<pcount;++i) {        objc_property_t Property=properties[i];        NSLog (@ "propertyname:%s", Property_getname (property));    NSLog (@ "propertyattributes:%s", property_getattributes (property)); }}

The final output results are as follows:

2015-08-12 12:56:45.147 uimenucontroller[1924:146558] Propertyname:myname

2015-08-12 12:56:45.147 uimenucontroller[1924:146558] propertyattributes:[email protected] "NSString", &,N, Vmyname

Explain:

in the example above, get propertyattributes as: [email protected] "NSString", &,n,vmyname

This is a char * type.

T : Start Letter

@ "NSString" :p the type of roperty. @ indicates that the property is an OC class, and "NSString" indicates the specific OC class name. For example:

ID myname;//@

Uicolor *myname;//@ "Uicolor"

Uitextfield *myname;//@ "Uitextfield"

Customclass *myname;//@ "Customclass", for custom type

int myname;//i, even if is the base data type, only the value of @encode (int) i

&: indicates that the property is retain (strong), except that C indicates that Copy,assign is not represented.

N: indicates nonatomic, if the atomic is not written.

vmyname: v starts with a property name

Additionally, read-write properties: ReadOnly is not written for R,readwrite.

This article is from the "Layne Learning Corner" blog, please be sure to keep this source http://laynestone.blog.51cto.com/9459455/1683972

Obtaining a list of properties for a class through the OC Runtime (runtime)