.h文件
#import <Foundation/Foundation.h>
NS_ASSUME_NONNULL_BEGIN
@interface NSArray (LYAarrayCategory)
@end
NS_ASSUME_NONNULL_END
.m文件
#import "NSArray+LYAarrayCategory.h"
#import <objc/runtime.h>
@implementation NSArray (LYAarrayCategory)
#pragma mark - Override Base Funtion
+(void)load{
[super load];
//获取要替换的系统方法
Method sysMethod1 = class_getInstanceMethod(objc_getClass("__NSArrayI"), @selector(objectAtIndex:));
Method sysMethod2 = class_getInstanceMethod(objc_getClass("__NSArrayI"), @selector(objectAtIndexedSubscript:));
//添加自己的方法
Method selfMethod1 = class_getInstanceMethod(objc_getClass("__NSArrayI"), @selector(ly_objectAtIndex:));
Method selfMethod2 = class_getInstanceMethod(objc_getClass("__NSArrayI"), @selector(ly_objectAtIndexedSubscript:));
//实现方法交换
method_exchangeImplementations(sysMethod1, selfMethod1);
method_exchangeImplementations(sysMethod2, selfMethod2);
}
#pragma mark - Action && Notification
-(id)ly_objectAtIndex:(NSInteger)index{
if (self.count - 1 < index) {
@try {
return [self ly_objectAtIndex:index];
} @catch (NSException *exception) {
NSLog(@"---------- %s Crash Because Method %s ----------\n",class_getName(self.class),__func__);
NSLog(@"---------- %@",[exception callStackSymbols]);
return nil;
} @finally {
NSLog(@"nothing to do");
}
}else{
return [self ly_objectAtIndex:index];
}
}
-(id)ly_objectAtIndexedSubscript:(NSInteger)index{
if (self.count - 1 < index) {
@try {
return [self ly_objectAtIndex:index];
} @catch (NSException *exception) {
NSLog(@"---------- %s Crash Because Method %s ----------\n",class_getName(self.class),__func__);
NSLog(@"---------- %@",[exception callStackSymbols]);
return nil;
} @finally {
NSLog(@"nothing to do");
}
}else{
return [self ly_objectAtIndex:index];
}
}
@end
