diff --git a/cachex.go b/cachex.go
index 3c91c9a..a72555c 100644
--- a/cachex.go
+++ b/cachex.go
@@ -12,11 +12,12 @@ import (
 // 到设定的点就删除
 
 type cache struct {
-	store sync.Map
+	prefix string
 }
 
 var one sync.Once
 var c *cache
+var store sync.Map
 
 type cacheData struct {
 	key    string
@@ -26,19 +27,22 @@ type cacheData struct {
 
 var ErrorEmpty error = errors.New("empty cache")
 
-func NewCache() *cache {
+func NewCache(prefix string) *cache {
+
+	c = &cache{
+		prefix: prefix,
+	}
+
 	one.Do(func() {
-		c = &cache{}
 
 		go func() {
 			for {
-				c.store.Range(func(key, value interface{}) bool {
+				store.Range(func(key, value interface{}) bool {
 					if value.(*cacheData).expire.Before(time.Now()) {
-						c.store.Delete(key)
+						store.Delete(key)
 					}
 					return true
 				})
-
 				time.Sleep(time.Second * 5)
 			}
 		}()
@@ -52,16 +56,18 @@ func (c *cache) Set(key string, value interface{}, expire time.Duration) {
 		expire = time.Hour * 24 * 365
 	}
 	cd := &cacheData{key, value, time.Now().Add(expire)}
-	c.store.Store(key, cd)
+	key = c.prefix + key
+	store.Store(key, cd)
 }
 
 // 读取缓存
 func (c *cache) Get(key string) (interface{}, error) {
-	if v, ok := c.store.Load(key); ok {
+	key = c.prefix + key
+	if v, ok := store.Load(key); ok {
 
 		cc := v.(*cacheData)
 		if cc.expire.Before(time.Now()) {
-			c.store.Delete(key)
+			store.Delete(key)
 			return nil, ErrorEmpty
 		}
 		return cc.data, nil
@@ -71,5 +77,17 @@ func (c *cache) Get(key string) (interface{}, error) {
 
 // 删除缓存
 func (c *cache) Delete(key string) {
-	c.store.Delete(key)
+	key = c.prefix + key
+	store.Delete(key)
+}
+
+// 清空缓存
+func (c *cache) Clear() {
+	store.Range(func(key, value interface{}) bool {
+		// 根据前缀删除
+		if key.(string)[:len(c.prefix)] == c.prefix {
+			store.Delete(key)
+		}
+		return true
+	})
 }
diff --git a/cachex_test.go b/cachex_test.go
index 4f3a059..86aa77c 100644
--- a/cachex_test.go
+++ b/cachex_test.go
@@ -9,12 +9,12 @@ import (
 )
 
 func TestCache(t *testing.T) {
-	cachex.NewCache().Set("test", "test", time.Second*5)
+	cachex.NewCache("").Set("test", "test", time.Second*5)
 
-	da, err := cachex.NewCache().Get("test")
+	da, err := cachex.NewCache("").Get("test")
 	fmt.Println(da, err)
 
 	time.Sleep(time.Second * 5)
-	da, err = cachex.NewCache().Get("test")
+	da, err = cachex.NewCache("").Get("test")
 	fmt.Println(da, err)
 }