优化随机字符串方法

utils/function.go

@@ -86,7 +86,7 @@ func Md5(encodeString string) string {
 }
 
 //GetRandomString 生成随机字符串
-func GetRandomString(num int) string {
+func GetRandomStringBack(num int) string {
 	str := "123456789abcdefghijklmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ"
 	bytes := []byte(str)
 	result := []byte{}
@@ -97,6 +97,22 @@ func GetRandomString(num int) string {
 	return string(result)
 }
 
+const str = "123456789abcdefghijklmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ"
+var (
+	randomBytes = []byte(str)
+	randT = rand.New(rand.NewSource(time.Now().UnixNano()))
+)
+
+//GetRandomString 生成随机字符串
+func GetRandomString(num int) string {
+
+	result :=  make([]byte,num)
+
+	for i := 0; i < num; i++ {
+		result[i] = randomBytes[int(randT.Int31())%num]
+	}
+	return string(result)
+}
 //CheckFileIsExist 判断文件是否存在  存在返回 true 不存在返回false
 func CheckFileIsExist(filename string) bool {
 	if _, err := os.Stat(filename); os.IsNotExist(err) {

utils/function_test.go

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2021. Lorem ipsum dolor sit amet, consectetur adipiscing elit.
+ * Morbi non lorem porttitor neque feugiat blandit. Ut vitae ipsum eget quam lacinia accumsan.
+ * Etiam sed turpis ac ipsum condimentum fringilla. Maecenas magna.
+ * Proin dapibus sapien vel ante. Aliquam erat volutpat. Pellentesque sagittis ligula eget metus.
+ * Vestibulum commodo. Ut rhoncus gravida arcu.
+ */
+
+package utils
+
+import "testing"
+
+
+func BenchmarkV1(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		GetRandomString(16) // run fib(30) b.N times
+	}
+}
+func BenchmarkV2(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		GetRandomStringV2(16) // run fib(30) b.N times
+	}
+}