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This article shares with you the content of a sample analysis of flow control in the Go language. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

1. Process control

Process control is the greatest invention in the programming language, because with it, you can express very complex logic through a very simple process description.

Process control can be divided into three categories: conditional judgment, loop control and unconditional jump.

2. If statement

If is perhaps the most common of all programming languages, and its syntax can be summarized as follows:

Do something if the conditions are met, otherwise do another thing.

Parentheses are not needed in the if condition judgment statement in Go, as shown in the following code:

If x > 10 {fmt.Println ("x is greater than 10")} else {fmt.Println ("x is less than 10")}

Another powerful aspect of Go's if is that it allows a variable to be declared in the conditional judgment statement. The scope of this variable can only be within the conditional logic block, but it will not work elsewhere as follows:

/ / calculate to get the value x, and then determine whether it is greater than 10 according to the size returned by x. If x: = computedValue (); x > 10 {fmt.Println ("x is greater than 10")} else {fmt.Println ("x is less than 10")} / / this place compiles an error if called in this way, because x is the variable fmt.Println (x) in the condition.

When there are multiple conditions, it is as follows:

If count = = 3 {fmt.Println ("The count is equal to 3")} else if count

< 3 { fmt.Println("The count is less than 3")} else { fmt.Println("The count is greater than 3")}3、goto Go 有 goto 语句——请明智地使用它。用 goto 跳转到必须在当前函数内定义的标签。 例如假设这样一个循环： func myFunc() {i := 0Here: //这行的第一个词，以冒号结束作为标签println(i)i++goto Here //跳转到 Here 去 } 标签名是大小写敏感的。 4、for语句 Go 里面最强大的一个控制逻辑就是 for，它即可以用来循环读取数据，又可以当作 while 来 控制逻辑，还能迭代操作。它的语法如下： for expression1; expression2; expression3 { //...} expression1、expression2 和 expression3 都是表达式，其中 expression1 和 expression3 是 变量声明或者函数调用返回值之类的，expression2 是用来条件判断，expression1在循环开始之前调用，expression3 在每轮循环结束之时调用。 一个例子比上面讲那么多更有用，那么我们看看下面的例子吧： package mainimport "fmt"func main(){ sum := 0; for index:=0; index < 10 ; index++ { sum += index} fmt.Println("sum is equal to ", sum)}// 输出：sum is equal to 45 有些时候需要进行多个赋值操作，由于 Go 里面没有,操作，那么可以使用平行赋值 i, j = i+1, j-1。有些时候如果我们忽略 expression1和expression3， 如下： sum := 1for ; sum < 1000; { sum += sum} 其中;也可以省略，那么就变成如下的代码了，是不是似曾相识？ 对，这就是 while 的功能。 sum := 1for sum < 1000 { sum += sum} 在循环里面有两个关键操作 break 和 continue ,break操作是跳出当前循环，continue是跳过本次循环。当嵌套过深的时候，break 可以配合标签使用，即跳转至标签所指定的位置， 详细参考如下例子： for index := 10; index >

0; index-- {if index = = 5 {break / / or continue} fmt.Println (index)} / / break print 10, 9, 8, 7, 6 continue print 10, 9, 8, 7, 6, 4, 3, 2, 1

Break and continue can also be labeled to jump to the outer loop in multiple loops, and for with range can be used to read data from slice and map:

For KJV map's key range map {fmt.Println ("map's val:", k) fmt.Println ("map's val:", v)}

Because Go supports multiple returns, and for variables that are declared but not called, the compiler reports an error, in which case you can use _ to discard unwanted return values such as:

For _, v: = range map {fmt.Println ("map's val:", v)} 5, switch

Sometimes you need to write a lot of if-else to implement some logical processing, when the code looks ugly and lengthy, and it is not easy to maintain in the future, switch can solve this problem very well.

Its syntax is as follows:

Switch sExpr {case expr1: some instructions case expr2: some other instructions case expr3: some other instructions default: other code}

The types of sExpr and expr1, expr2, and expr3 must be the same. Go's switch is very flexible, and expressions don't have to be constants or integers to perform the process from top to bottom until a match is found; and if switch doesn't have an expression, it matches true.

I: = 10switch I {case 1: fmt.Println ("i is equal to 1") case 2,3,4: fmt.Println ("i is equal to 2,3 or 4") case 10: fmt.Println ("i is equal to 10") default: fmt.Println ("All I know is that i is an integer")}

In the above code, we aggregate a lot of values into one case. At the same time, switch in Go is equivalent to each case with break by default. After a successful match, it will not automatically execute other case down, but jump out of the entire switch, but you can use fallthrough to enforce the following case code.

Integer: = 6switch integer {case 4: fmt.Println ("The integer was

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