feat(string): add stringx option

pkg/structure/interface.gen.go

@@ -21,4 +21,6 @@ type StringXInterface interface {
 	Reduce(int32) (string, error)
 	Setbit(int32, bool) UpdateLength
 	Getbit(int32) (bool, error)
+	Getrange(start, end int32) (string, error)
+	GetLength() int
 }

pkg/structure/stringx/string.go

@@ -1,9 +1,10 @@
 package stringx
 
 import (
+	"strconv"
+
 	"gitee.com/timedb/wheatCache/pkg/errorx"
 	"gitee.com/timedb/wheatCache/pkg/structure"
-	"strconv"
 )
 
 type StringSingle struct {
@@ -17,7 +18,7 @@ func NewStringSingle() structure.StringXInterface {
 }
 
 func (s *StringSingle) SizeByte() int64 {
-	return int64(s.val.GetLength())
+	return int64(s.val.GetSize())
 }
 
 // RollBack TODO 事务相关, V2 实现
@@ -105,3 +106,15 @@ func (s *StringSingle) Getbit(offer int32) (bool, error) {
 
 	return b, err
 }
+
+func (s *StringSingle) Getrange(start, end int32) (string, error) {
+	b, err := s.val.SliceByString(int(start), int(end))
+	if err != nil {
+		return "", err
+	}
+	return string(b), nil
+}
+
+func (s *StringSingle) GetLength() int {
+	return s.val.GetLength()
+}

pkg/structure/value.go

@@ -3,9 +3,10 @@ package structure
 import (
 	"bytes"
 	"encoding/binary"
-	"gitee.com/timedb/wheatCache/pkg/errorx"
 	"math"
 	"strconv"
+
+	"gitee.com/timedb/wheatCache/pkg/errorx"
 )
 
 // Value 提供一个基础的 动态类型
@@ -28,6 +29,10 @@ func (v *Value) GetLength() int {
 	return len(v.val)
 }
 
+func (v *Value) GetSize() int {
+	return v.length
+}
+
 func (v *Value) GetDynamicType() DynamicType {
 	return v.onType
 }
@@ -160,3 +165,17 @@ func (v *Value) GetByte(offset int) (bool, error) {
 
 	return false, errorx.New("the maximum length is exceeded")
 }
+
+func (v *Value) SliceByString(start, end int) ([]byte, error) {
+	if v.onType != DynamicString {
+		return nil, errorx.New("not is string")
+	}
+	if start > end {
+		return nil, errorx.New("the end cannot be greater than the beginning")
+	}
+	if end > v.length {
+		return nil, errorx.New("the maximum index is exceeded, max index: %d", v.length)
+	}
+
+	return v.val[start:end], nil
+}