// Created by 张国锋 on 15-7-23.
// Copyright (c) 2014年 张国锋. All rights reserved.
//
#import "AppDelegate.h"
#import "RootViewController.h"
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
RootViewController *root = [[RootViewController alloc] init];
self.window.rootViewController =root;
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
}
//
// RootViewController.m
// DBTransaction -FMDB
//
// Created by 张国锋 on 15-7-23.
// Copyright (c) 2014年 张国锋. All rights reserved.
//
#import "RootViewController.h"
#import "FMDatabase.h"
//需要导入libsqlite3.dylib系统库
@interface RootViewController ()
{
FMDatabase *_dataBase;
}
@end
@implementation RootViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
NSString *dbPath = [NSHomeDirectory() stringByAppendingFormat:@"/Documents/test.db"];
//初始化
_dataBase = [[FMDatabase alloc] initWithPath:dbPath];
if ([_dataBase open]) {
//创建表
NSString *createSql = @"create table if not exists student(id integer,name varchar(256))";
if (![_dataBase executeUpdate:createSql]) {
NSLog(@"create error:%@",_dataBase.lastErrorMessage);
}
}
//NSDate 时间类
NSDate *date1 = [NSDate date];//获取系统当前时间
[self insertDataWithCount:1000 isUseTransaction:YES];
NSDate *date2 = [NSDate date];
//取到时间的差值 (timeIntervalSinceDate 两个时间的差值，单位是秒)
//NSTimeInterval 时间差变量，秒
NSTimeInterval time = [date2 timeIntervalSinceDate:date1];
NSLog(@"time:%f",time);
// Do any additional setup after loading the view.
}
//插入批量数据，是否手动启用事务
- (void)insertDataWithCount:(NSInteger)count isUseTransaction:(BOOL)isUse{
if (isUse) {
//手动启用事务
BOOL isError = NO;
@try {
//写可能出现异常的代码
[_dataBase beginTransaction];//手动开启一个事务
for (int i=0; i<count; i++) {
NSString *idStr =[NSString stringWithFormat:@"%d",i];
NSString *stName = [NSString stringWithFormat:@"student%d",i];
NSString *insertSql = @"insert into student(id,name) values(?,?)";
if (![_dataBase executeUpdate:insertSql,idStr,stName]) {
NSLog(@"insert error:%@",_dataBase.lastErrorMessage);
}
}
}
@catch (NSException *exception) {
//捕获到异常
NSLog(@"error:%@",exception.reason);
isError = YES;
[_dataBase rollback];//回滚，回到最初的状态
}
@finally {
//无论有没有异常，代码都会执行到此处
if (isError==NO) {
[_dataBase commit];//提交事务，让批量操作生效
}
}
}else{
//常规操作
for (int i=0; i<count; i++) {
NSString *idStr =[NSString stringWithFormat:@"%d",i];
NSString *stName = [NSString stringWithFormat:@"student%d",i];
NSString *insertSql = @"insert into student(id,name) values(?,?)";
if (![_dataBase executeUpdate:insertSql,idStr,stName]) {
NSLog(@"insert error:%@",_dataBase.lastErrorMessage);
}
}
}
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
//清除缓存
[[SDImageCache sharedImageCache]getSize]
{
[[SDImageCache sharedImageCache] clearDisk];
[[SDImageCache sharedImageCache] clearMemory];
[[NSURLCache sharedURLCache] removeAllCachedResponses];
//清除cookies
NSHTTPCookie *cookie;
NSHTTPCookieStorage *storage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (cookie in [storage cookies]) {
[storage deleteCookie:cookie];
}
}
+ (void)cancelWebCache
{
[[NSURLCache sharedURLCache] removeAllCachedResponses];
//清除cookies
NSHTTPCookie *cookie;
NSHTTPCookieStorage *storage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (cookie in [storage cookies]) {
[storage deleteCookie:cookie];
}
}
转载于:https://www.cnblogs.com/0515offer/p/4695949.html
