From ce422881bc6db66ea506f8406a8ab919ff6089a5 Mon Sep 17 00:00:00 2001
From: gazebo <gazeboxu@gmail.com>
Date: Sun, 31 Mar 2019 12:13:28 +0800
Subject: [PATCH] - LimitUTF8StringLen

---
 utils/utils.go      | 21 +++++++++++++++++++++
 utils/utils_test.go | 30 ++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/utils/utils.go b/utils/utils.go
index 8228d086..1224bf32 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -246,3 +246,24 @@ func Base64DecodeMultiString(strs ...string) (decodedData [][]byte, err error) {
 	}
 	return decodedData, nil
 }
+
+func LimitStringLen(str string, maxLen int) (limitedStr string) {
+	if maxLen > 0 {
+		if strLen := len(str); strLen > maxLen {
+			str = str[:maxLen]
+		}
+	}
+	return str
+}
+
+func LimitUTF8StringLen(str string, maxLen int) (limitedStr string) {
+	if maxLen > 0 {
+		if len(str) > maxLen {
+			runeList := []rune(str)
+			if len(runeList) > maxLen {
+				str = string(runeList[:maxLen])
+			}
+		}
+	}
+	return str
+}
diff --git a/utils/utils_test.go b/utils/utils_test.go
index cc3e60dd..16a906e1 100644
--- a/utils/utils_test.go
+++ b/utils/utils_test.go
@@ -185,3 +185,33 @@ func TestStruct2MapByJson(t *testing.T) {
 	})
 	t.Log(mapData)
 }
+
+func TestLimitUTF8StringLen(t *testing.T) {
+	for _, v := range [][]interface{}{
+		[]interface{}{
+			"123456789",
+			6,
+			"123456",
+		},
+		[]interface{}{
+			"123456789",
+			0,
+			"123456789",
+		},
+		[]interface{}{
+			"一二345六789",
+			6,
+			"一二345六",
+		},
+		[]interface{}{
+			"1二345六789",
+			0,
+			"1二345六789",
+		},
+	} {
+		str := LimitUTF8StringLen(v[0].(string), v[1].(int))
+		if str != v[2] {
+			t.Fatalf("%v处理错误，预期:%v，实际:%s", v[0], v[2], str)
+		}
+	}
+}