From fe97a6748d106e9edaeeec5b6a9b7c2d451bbdb1 Mon Sep 17 00:00:00 2001
From: devlights <gsf.zero1@devlights.onmicrosoft.com>
Date: Wed, 14 Aug 2024 15:44:17 +0000
Subject: [PATCH] Add string_random_string example

---
 examples/basic/strs/README.md        |  1 +
 examples/basic/strs/examples.go      |  1 +
 examples/basic/strs/random_string.go | 46 ++++++++++++++++++++++++++++
 3 files changed, 48 insertions(+)
 create mode 100644 examples/basic/strs/random_string.go

diff --git a/examples/basic/strs/README.md b/examples/basic/strs/README.md
index e0900e9e..d1475ad0 100644
--- a/examples/basic/strs/README.md
+++ b/examples/basic/strs/README.md
@@ -13,3 +13,4 @@
 | diff_trimright_trimsuffix.go | string_diff_trimright_trimsuffix | strings.TrimRight と strings.TrimSuffix のちょっとした違いについてのサンプルです. |
 | using_string_clone.go        | string_using_clone               | Go 1.18 で追加された strings.Clone() のサンプルです                               |
 | trimspace.go                 | string_trim_space                | strings.TrimSpace() のサンプルです.                                               |
+| random_string.go             | string_random_string             | 指定された文字数のランダム文字列を作成するサンプルです.                           |
diff --git a/examples/basic/strs/examples.go b/examples/basic/strs/examples.go
index 53bdaf37..73df3bbd 100644
--- a/examples/basic/strs/examples.go
+++ b/examples/basic/strs/examples.go
@@ -23,4 +23,5 @@ func (r *register) Regist(m mapping.ExampleMapping) {
 	m["string_cut_prefix_suffix"] = CutPrefixSuffix
 	m["string_using_clone"] = UsingStringsClone
 	m["string_trim_space"] = TrimSpace
+	m["string_random_string"] = RandomString
 }
diff --git a/examples/basic/strs/random_string.go b/examples/basic/strs/random_string.go
new file mode 100644
index 00000000..0b1dbcbf
--- /dev/null
+++ b/examples/basic/strs/random_string.go
@@ -0,0 +1,46 @@
+package strs
+
+import (
+	"math/rand"
+	"time"
+
+	"github.com/devlights/gomy/output"
+)
+
+// RandomString は、指定された文字数のランダム文字列を作成するサンプルです.
+//
+// # REFERENCES
+//   - https://gist.github.com/devlights/7534500bfe62c566bf944553ae8974e8
+func RandomString() error {
+	const (
+		charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	)
+
+	var (
+		buf       = make([]byte, 1<<6)
+		unixNano  = time.Now().UnixNano()
+		rndSource = rand.NewSource(unixNano)
+		rnd       = rand.New(rndSource)
+	)
+
+	for i := range buf {
+		buf[i] = charset[rnd.Intn(len(charset))]
+	}
+
+	output.Stdoutl("[output]", string(buf))
+
+	return nil
+
+	/*
+	   $ task
+	   task: [build] go build .
+	   task: [run] ./try-golang -onetime
+
+	   ENTER EXAMPLE NAME: string_random_string
+
+	   [Name] "string_random_string"
+	   [output]             0OWayZgY57QSJKHvAl8ePRtFSFGtgKJRug6OFdN3XL17oxUW2pqmCaGpGqYV2oEY
+
+	   [Elapsed] 28.55µs
+	*/
+}