iOS - 客户端网络请求 - 数据处理

[self loadFromDb];
if (![[Helper isExistenceNetwork] isEqualToString:@"NotReachable"]) {
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[self loadFromService];
});
}

#pragma mark - 读取数据库

- (void)loadFromDb
{
FMDatabase *db = [FMDatabase databaseWithPath:dbPath];
if (![db open]) {
NSLog(@"Could not open db.");
return;
}

FMResultSet *blogListResult;

blogListResult = [db executeQueryWithFormat:@"select语句];

blogsData = [[NSMutableDictionary alloc] init];
oldListSource = [[NSMutableArray alloc] init];

while ([blogListResult next]) {
NSMutableDictionary *blogsDic = [[NSMutableDictionary alloc] init];

// 组装数据

[blogsDic setObject:STATUS_DELETE forKey:@"status"];
NSString *key =[NSString stringWithFormat:@"%@", [blogsDic objectForKey:@"id"]];
[blogsData setObject:blogsDic forKey:key];
[blogsListSource addObject:blogsDic];
[oldListSource addObject:blogsDic];
}

[db close];
[self reloadSource];
}

- (void)requestFinished:(ASIHTTPRequest *)request
{
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
NSDictionary *result = [[[NSString alloc] initWithData:[request responseData] encoding:NSUTF8StringEncoding] objectFromJSONString];
NSArray *blogListAry = [result objectForKey:@"blogList"];

BOOL isChanged = NO;
FMDatabase *db = [FMDatabase databaseWithPath:dbPath];
if (![db open]) {
NSLog(@"Could not open db.");
return;
}

if ([blogListAry count] != [oldListSource count]) {
isChanged = YES;
}

for (int i = 0; i < [blogListAry count]; i++) {
NSDictionary *blogs = [blogListAry objectAtIndex:i];
if ([blogsData objectForKey:[NSString stringWithFormat:@"%@", [blogs objectForKey:@"id"]]]) {
NSMutableDictionary *oldSpace = [blogsData objectForKey:[NSString stringWithFormat:@"%@", [blogs objectForKey:@"id"]]];
//更新本地数据库
isChanged = YES;
　　　　　　　　　　//改变oldSpace中key的值也就相当于改变了oldListSource中key的值
[oldSpace setObject:STATUS_NORMAL forKey:@"status"];
}else{
//插入本地数据库
isChanged = YES;
}
}

if (isChanged) {
for (int i = 0; i < [oldListSource count]; i++) {
NSMutableDictionary *oSpace = [oldListSource objectAtIndex:i];
if ([[oSpace objectForKey:@"status"] isEqualToString:STATUS_DELETE]) {
　　　　　　　　　　　　//删除数据库多余的数据
}
}
dispatch_async(dispatch_get_main_queue(), ^{
[self loadFromDb];
});
}
});
}