iOS知识复习总结（七）线程
1.NSOperation
//并行队列（只有并行队列）
NSOperationQueue *queue = [NSOperationQueue new];
//任务
NSBlockOperation *op1 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op1 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op1 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op2 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op2 begin %@", [NSThread currentThread]);
sleep(4);
NSLog(@"op2 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op3 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op3 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op3 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op4 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op4 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op4 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op5 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op5 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op5 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op6 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op6 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op6 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op7 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op7 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op7 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op8 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op8 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op8 end %@", [NSThread currentThread]);
}];
NSBlockOperation *op9 = [NSBlockOperation blockOperationWithBlock:^{
NSLog(@"op9 begin %@", [NSThread currentThread]);
sleep(2);
NSLog(@"op9 end %@", [NSThread currentThread]);
}];
/*
[queue addOperation:op1];
[queue addOperation:op2];*/
//waitUntilFinished：下方的代码是否要等待队列中的任务完成后再执行
//线程的最大并发数量，最佳值3~5
queue.maxConcurrentOperationCount = 3;
//添加依赖 让op1任务 需要在op8 op5都完成之后才能执行
[op1 addDependency:op8];
[op1 addDependency:op5];
[queue addOperations:@[op1, op2, op3, op4, op5, op6, op7, op8, op9] waitUntilFinished:NO];
NSLog(@"waitUntilFinished");
//取消队列中的所有任务
[queue cancelAllOperations];
//取消队列中的一些任务
[op3 cancel]; //已经开始执行的任务，不能单独取消
[op6 cancel];
//暂停队列 suspended:暂停
queue.suspended = YES;
sleep(10);
queue.suspended = NO;
dispatch_async(dispatch_get_global_queue(0, 0), ^{
dispatch_async(dispatch_get_main_queue(), ^{
});
});
[[NSOperationQueue new] addOperationWithBlock:^{
NSLog(@"%@", [NSThread currentThread]);
[[NSOperationQueue mainQueue] addOperationWithBlock:^{
}];
}];
2.GCD
