GCD-block, adblock

GCD-block, adblock

1. block Definition

 

// Declare the variable (void) (^ PrintStr) (void); // define PrintStr =^{ NSLog (@ "PrintStr") ;}; // call PrintStr ();

 

2. Modify variables outside the block

The variables in the block do not take effect outside the block. You can add _ block to make it take effect.

 

Int a = 0; void (^ foo) (void) = ^ {a = 1;} // The value of a in foo () is 0foo (); __block int a = 0; void (^ foo) (void) = ^ {a = 1;} // The value of a in foo () is changed to 1foo ();

 

References:

Http://www.devtang.com/blog/2012/02/22/use-gcd/