IOS Multithreading (Nsoperationqueue)

1. Basic use

Nsinvocationoperation

1. Create an Action object that encapsulates the task that needs to be performed    Nsinvocationoperation * Operation =[[nsinvocationoperation alloc]initwithtarget:self Selector: @selector (download) Object:nil];        2. Perform the action (by default, if the action is not placed in the queue, it is synchronous)    [Operation start];-(void) download{    NSLog (@ "--------Download picture-----%@" , [Nsthread CurrentThread]);}

Nsblockoperation

1. Package Operation    Nsblockoperation * operation=[nsblockoperation blockoperationwithblock:^{        NSLog (@ "-------- Download picture-----%@ ", [Nsthread CurrentThread]);    }];        [Operation addexecutionblock:^{         NSLog (@ "--------Download picture 1-----%@", [Nsthread CurrentThread]);    }];    [Operation addexecutionblock:^{         NSLog (@ "--------Download picture 2-----%@", [Nsthread CurrentThread]);    }];        2. Perform the Operation    [operation start];        Note: An operation is performed asynchronously as long as the nsblockoperation encapsulates the operand >1

Nsoperationqueue Operation queue

Create an action queue    nsoperationqueue * Queue =[[nsoperationqueue alloc]init];    Nsinvocationoperation *operation1 =[[nsinvocationoperation alloc]initwithtarget:self selector: @selector (download) Object:nil];    Nsinvocationoperation * Operation2 =[[nsinvocationoperation alloc]initwithtarget:self selector: @selector (Run) object : nil];        Nsblockoperation * Operation3 =[nsblockoperation blockoperationwithblock:^{        NSLog (@ "--------Download picture 2-----%@", [ Nsthread CurrentThread]);            }];        [Operation3 addexecutionblock:^{        NSLog (@ "--------run2-----%@", [Nsthread CurrentThread]);    }];            [Queue Addoperation:operation1];    [Queue Addoperation:operation2];    [Queue Addoperation:operation3]; Put the action in the queue to operate asynchronously

* Set the maximum number of concurrent

-(void) Setmaxconcurrentoperationcount: (Nsinteger) CNT;

* Set Dependencies

[Opetationb adddependency:operationa];//Operation B relies on operation a a executes before execution B

IOS Multithreading (Nsoperationqueue)