iOS Development--Grammar OC Chapter &block Review

Block review

Here is a brief introduction to the syntax of block, if you think it is very simple or want to learn more in-depth use of inventory to see the reporter before the use of block values and advanced block use:

Http://www.cnblogs.com/iCocos/p/4534281.html

Http://www.cnblogs.com/iCocos/p/4550169.html

Http://www.cnblogs.com/iCocos/p/4659878.html

Http://www.cnblogs.com/iCocos/p/4655846.html

• Block:block function, code block
• Block is a "special" object

Function:

• 1. No return value no parameters
• 2. No return value has parameters
• 3. There are parameters to return

Block:

• 1. No return value no parameters
• 2. No return value has parameters
• 3. There are parameters to return

No return value no parameter

C Language Functions:

1 // No return value no parameter function 2 void say1 () {3     NSLog (@ "say1 ... " ); 4 }

    // calling Functions     say1 ();    

OC code block:

1 //1. No return value no parameter block2 3 voidtest1 () {4 5     //1. No return value no parameter block6 7     void(^say1block) () = ^{8 9NSLog (@"Say1block ...");Ten  One     }; A  -     //Call Block -  the Say1block (); -  -}

No return value has parameters

C Language Functions:

1 // no return value with parametric function 2 3 void say2 (int age ) {45     NSLog (@ "I ' am%d year old! " , age); 6 7 }

        // called    Say2 ();

OC code block:

1 //2. No return value with parameter block2 3 voidtest2 () {4 5 6     void(^say2block) (int) = ^(intAge ) {7 8NSLog (@"I ' am%d year old!", age);9 Ten     }; One  A  -Say2block ( -); -  the   -  -}

There are return values with parameters

C language functions:

1 // There are return values with parametric functions 2 3 int sum (int A,int  b) {45     return a + b; 6 7 }89  

OC code block:

1 //3. There is a return parameter block2 3 voidtest3 () {4 5       int(^sumblock) (int,int) = ^(intAintb) {6 7             returnA +b;8 9         };Ten  One         intRESULT1 = SUM (Ten,Ten); A  -         intRESULT2 = Sumblock ( One, One); -  theNSLog (@"result1:%d result2:%d", RESULT1,RESULT2); -  -          -  +         //typedef a block -  +   A  at         //Redefine "No return value" without parameter Block -  -typedefvoid(^Say2block) (); -  -          -  inSay2block block = ^{ -  toNSLog (@"Say2block ========"); +  -         }; the  *          $ Panax Notoginseng block (); -  the}

iOS Development--Grammar OC Chapter &block Review