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