diff --git a/hash/sha256/sha256.go b/hash/sha256/sha256.go
index aa26dc0..6234924 100644
--- a/hash/sha256/sha256.go
+++ b/hash/sha256/sha256.go
@@ -46,8 +46,7 @@ func Sha256_224Hex(data []byte) string {
 
 // 根据给定位数计算一个字节数组的Sha256校验和，返回字节数组。
 func Sum256(data []byte, bitSize ...int) []byte {
-	length := append(bitSize, 256)
-	hasher := hasherSelect(length[0])
+	hasher := hasherSelect(append(bitSize, 256)[0])
 	hasher.Write(data)
 	return hasher.Sum(nil)
 }
@@ -65,7 +64,7 @@ func SumFile256(file string, bitSize ...int) ([]byte, error) {
 	}
 	defer f.Close()
 
-	hasher := hasherSelect(bitSize[0])
+	hasher := hasherSelect(append(bitSize, 256)[0])
 	if _, err := io.Copy(hasher, f); err != nil {
 		return nil, fmt.Errorf("未能读取指定文件的内容，%w", err)
 	}