Go Range Function Usage

This is a creation in Article, where the information may have evolved or changed.

The range function is a magical and interesting built-in function that you can use to iterate through arrays, slices, and dictionaries.

When used to iterate over arrays and slices, the range function returns indexes and elements;

When used to traverse a dictionary, the range function returns the key and value of the dictionary.

<textarea wrap= "soft" class= "Crayon-plain print-no" data-settings= "DblClick" readonly style= "-MOZ-TAB-SIZE:4; -o-tab-size:4; -webkit-tab-size:4; Tab-size:4; FONT-SIZE:12PX!important; line-height:15px!important; " >package mainimport ("FMT") func main () {//Here we use range to calculate all the elements of a slice and//This method applies to the array also nums: = []int{2, 3, 4} Sum: = 0 for _, num: = range nums {sum + = num} fmt. Println ("sum:", sum)//range returns index and element values when iterating through arrays and slices//If we do not care about the index can use an underscore (_) to ignore this return value//Of course we sometimes need this index for I, Num: = range nums {if num = = 3 {fmt. Println ("Index:", I)}}//When using range to traverse the dictionary, return the key-value pairs. KVS: = map[string]string{"A": "Apple", "B": "Banana"} for K, V: = range KVS {fmt. Printf ("%s-%s\n", K, V)}//The range function is used to iterate through a string, returning a Unicode code point. The first return value is the index of the starting byte of each character, the second is the character code point,//Because the string of go is made up of bytes, and multiple bytes form a rune type character. For I, C: = Range "Go" {fmt. Println (i, c)}} </textarea>

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Package MainImport (    "FMT")funcMain() {    //Here we use range to calculate all the elements of a slice and    //This method is also applicable to arrays    Nums := []int{2, 3, 4}    sum := 0     for _, Num := Range Nums {        sum += Num    }    FMT.Println("sum:", sum)    //Range returns index and element values when iterating through arrays and slices    //If we don't care the index can use an underscore (_) to ignore this return value    //Of course we sometimes need this index     for I, Num := Range Nums {        if Num == 3 {            FMT.Println("Index:", I)        }    }    returns a key-value pair when using range to traverse the dictionary.     KVS := Map[string]string{"a": "Apple", "B": "Banana"}     for k, v := Range KVS {        FMT.Printf("%s-%s\n", k, v)    }    the//Range function returns a Unicode code point when it is used to traverse a string.     The first return value is the index of the starting byte of each character, and the second is the character code point .    //Because the string of go is made up of bytes, multiple bytes form a rune type character.      for I, C := Range "Go" {        FMT.Println(I, C)    }}

The output is:

<textarea wrap="soft" class="crayon-plain print-no" data-settings="dblclick" readonly="" style="-moz-tab-size:4; -o-tab-size:4; -webkit-tab-size:4; tab-size:4; font-size: 12px !important; line-height: 15px !important;">banana0 1031, Appleb,/usr/local/go/bin/go run/users/xiequan/mygo/src/golangdemo/main.gosum:9index:1a 111</textarea>

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/usr/Local/Go/bin/GoRun /Users/Xiequan/Mygo/src/Golangdemo/Main.Gosum: 9Index: 1a - Appleb - Banana0 1031 111

Go Range Function Usage