viewDidAppear打印当前页面类名，dealloc时打印销毁画页，看是否有离开未销毁可能存在内存泄漏的页面

UIViewController+Hook.h

#import <UIKit/UIKit.h>

/**
 viewDidAppear打印当前页面类名，dealloc时打印销毁画页，看是否有离开未销毁可能存在内存泄漏的页面
 */
@interface UIViewController (Hook)

@end

UIViewController+Hook.m

#import "UIViewController+Hook.h"
#import <objc/runtime.h>


#ifdef DEBUG
#if 0 // 0 详细输出 1 简洁输出
#define SXLog(FORMAT, ...) fprintf(stderr,"\n文件:\t%s\t 行数: %d 方法:\t%s \n输出:\t%s\n",[[[NSString stringWithUTF8String:__FILE__] lastPathComponent] UTF8String], __LINE__,__FUNCTION__, [[NSString stringWithFormat:FORMAT, ##__VA_ARGS__] UTF8String]);
#else
#define SXLog(FORMAT, ...) fprintf(stderr,"%s\n", [[NSString stringWithFormat:FORMAT, ##__VA_ARGS__] UTF8String]);
#endif
#else
#define SXLog(...)
#endif


@implementation UIViewController (Hook)
//静态就交换静态，实例方法就交换实例方法
void Swizzle_(Class c, SEL origSEL, SEL newSEL)
{
    Method origMethod = class_getInstanceMethod(c, origSEL);
    Method newMethod = nil;
    if (!origMethod) {
        origMethod = class_getClassMethod(c, origSEL);
        if (!origMethod) {
            return;
        }
        newMethod = class_getClassMethod(c, newSEL);
        if (!newMethod) {
            return;
        }
    }else{
        newMethod = class_getInstanceMethod(c, newSEL);
        if (!newMethod) {
            return;
        }
    }
    
    //自身已经有了就添加不成功，直接交换即可
    if(class_addMethod(c, origSEL, method_getImplementation(newMethod), method_getTypeEncoding(newMethod))){
        class_replaceMethod(c, newSEL, method_getImplementation(origMethod), method_getTypeEncoding(origMethod));
    }else{
        method_exchangeImplementations(origMethod, newMethod);
    }
}
#ifdef DEBUG
+ (void)load {
    
    static dispatch_once_t onceToken;  dispatch_once(&onceToken, ^{
        
        Class class = [self class];
        // 进入画页，快速定位当前要修改的页面名字
        Swizzle_(class, NSSelectorFromString(@"viewDidAppear:"), @selector(myViewDidAppear:));
        // 画页销毁，是否存在不释放现象
        Swizzle_(class, NSSelectorFromString(@"dealloc"), @selector(myDealloc));
        
    });
}
- (void)myViewDidAppear:(BOOL)animated {
    SXLog(@"----进入画页%@---", [self class]);
    
    [self myViewDidAppear:animated];
}
- (void)myDealloc {
    SXLog(@"----销毁画页%@---", [self class]);
    
    [self myDealloc];
}
#endif

@end