Simple use of IOS block and __block and static modifier variables

Simple code Summary, the shortcomings of a lot of advice.

//Simple to use-(void) blockone{intNumber= at; int(^blockone) (int) = ^(intnum2) {                returnnumber*num2;            }; NSLog (@"block%d for output", Blockone (2)); }-(void) blocktwo{int(^block) (int,int) = ^(intStra,intstr2) {                returnStra +str2;            }; NSLog (@"This is the second one.%d", Block (2,3)); }-(void) blockthree{//this represents the square root of the input (int A is the parameter, return a*a; is the subject of the action). Remember to add ";" because it is a narrative, and the whole {} is followed by a ";" because block is an object entity.//the 3 inside the parentheses will be treated as an input value and then the block output 3*3=9 call the reblock variable.            intReblock = ^ (intA) {returnA*a;} (3); NSLog (@"reblock%d", reblock); //the above simple method callback value (^ name) (parameter column);        int(^square) (int); //there is a square block Pointer The block it points to has an int input and outputSquare= ^(intA) {returnA*a;};//Put the entity just now to square//UseNSLog (@"Square%d of output square", Square (2)); }

Changes in the value of a variable in a block inside and outside the function

-(void) blockpointer{#defineWhether the change of the mark variable can change its value//1 unmodified Block outside change Outa does not change the final result       intOutA =8;
    int(^MYPTR) (int) = ^(inta) {returnOutA +A;        }; OutA=Ten;
    //go to a block in the same scope value

    intresult = Myptr (3);
NSLog (@"block outside the change outa value of 10 will be 13 after%d", result);///This value will be copied to block for the first time in the block, and the next time you use the copy value directly, the value of the defense is not affected by the value of the variable; if it is a pointer pointer, its value can be changed in the Block        //2 __block Modified after modification, can change in the inside change, can change//external Changes__blockintOutB =8;
    int(^MYPTRB) (int) = ^(intb) {
        returnOutB +b;        }; OutB=Ten;
    //go to a block in the same scope value    intRESULTB = MYPTRB (3); NSLog (@"block outside the change OUTB value of 10 will be 13 after%d", RESULTB); //Block Internal Change__blockintOUTC =8; int(^MYPTRC) (int) = ^(intc) {OUTC=Ten; returnOUTC +C;              }; NSLog (@"block Internal variable OUTC value of 10 will be 13 after%d", MYPTRC (3)); }

#defineChange in value when Mark static modifies a variable//modification with Staic is a change, because OUTC is a static variable that responds directly to its value .-(void) blockstaticchange{//2 __block Modified after modification, can change in the inside change, can change//external Changes   Static  intOutB =8; int(^MYPTRB) (int) = ^(intb) {returnOutB +b;        }; OutB=Ten; //go to a block in the same scope value    intRESULTB = MYPTRB (3); NSLog (@"static external Change outb value of 10 will be 13 after%d", RESULTB); //Block Internal Change            Static intOUTC =8; int(^MYPTRC) (int) = ^(intc) {OUTC=Ten; returnOUTC +C;        }; NSLog (@"static internal variable OUTC value of 10 will be 13 after%d", MYPTRC (3)); }

Simple use of IOS block and __block and static modifier variables