IOS development-code block usage

[Java] <P style = "TEXT-ALIGN: left; PADDING-BOTTOM: 0px; LINE-HEIGHT: 26px; BORDER-RIGHT-WIDTH: 0px; LIST-STYLE-TYPE: none; MARGIN-TOP: 0px; FONT-FAMILY: Arial; WORD-WRAP: normal; MARGIN-BOTTOM: 0px; BORDER-TOP-WIDTH: 0px; BORDER-BOTTOM-WIDTH: 0px; COLOR: rgb (, 73); FONT-SIZE: 14px; WORD-BREAK: normal; BORDER-LEFT-WIDTH: 0px; PADDING-TOP: 0px "> </P> <PRE class = plain name =" code "> </PRE> <PRE class = jav A name = "code">/* print numbers in the code */NSLog (@ "------------------ resultBlocks -------------------->"); int (^ resultBlocks) (int) = ^ (int num) {return num * 20;}; int resultNum = resultBlocks (2); NSLog (@ "result: % 4d", resultNum ); NSLog (@ "-------------- myprintBlock -------------------->"); void (^ myprintBlock) (NSString * x) = ^ (NSString * str) {NSLog (@ "@ printBlock: % @", str) ;}; myprintBlock (@ "Hello block"); NSLog (@" --------------- PrintNumBlock ---------------------> ");/* separate multiple parameters in code with commas */void (^ printNumBlock) (int, int); printNumBlock = ^ (int num, int num2) {num = num + num2; NSLog (@ "printNum: % d", num) ;}; printNumBlock (random, 1000 ); NSLog (@ "----------------- recursive use --------------------->");/** you should pay attention to the code when using recursion. initialize the entire code before calling it, otherwise it will run incorrectly! How does one end wrong? 1: Use the sataic keyword to initialize the class before initialization. 2: Use the _ block keyword */_ block void (^ const blocks) (int) = ^ (int I) {if (I> 0) {NSLog (@ "num: % d", I); blocks (I-1 );}}; blocks (4); static void (^ const blocks2) (int) = ^ (int I) {if (I> 0) {NSLog (@ "num: % d ", i); blocks2 (I-1) ;}}; blocks2 (4); NSLog (@ "--------------- sortArray -----------------------> "); /* sort string arrays in code fast */NSArray * stringArray = [NSArray arrayWithObjects: @ "abc 1", @ "abc 21", @ "abc 12 ", @ "abc 13", @ "abc 0.5", nil]; NSComparator sortBlcok = ^ (id String1, id String2) {return [String1 compare: String2];}; NSArray * sortArray = [stringArray Arrays: sortBlcok]; NSArray * sortArray2 = [stringArray Arrays: ^ (id String1, id String2) {return [String1 compare: String2];}]; NSLog (@ "stringArray: % @", stringArray); NSLog (@ "sortArray: % @", sortArray2); NSLog (@ "------ changeGlobalBlock ---------------------------> "); /* edit all local variables in code fast */void (^ changeGlobalBlock) (void) = ^ (void) {global ++ ;}; changeGlobalBlock (); NSLog (@ "changeGlobalBlock: % d", global); NSLog (@ "------ changLocalNumBlock --------------------------->");/* Compilation of local variable changes in the Code is not acceptable, you need to add the _ block keyword before it. Otherwise, the following error will be reported: Variable is not assignable (miss_block type specifier */www.2cto.com _ block int localNum = 500; void (^ changLocalNumBlock) (int) = ^ (int I) {localNum = localNum + I ;}; changLocalNumBlock (30); NSLog (@ "changLocalNumBlock: % d", localNum ); </PRE> <PRE class = java name = "code"> refer to this blog: </PRE> <PRE class = java name = "code"> http://blog.sina.com.cn/s/blog_71715bf8010166ux.html </PRE>