diff --git a/wchat/common/HttpClient.php b/wchat/common/HttpClient.php
index c045a7e..68837da 100644
--- a/wchat/common/HttpClient.php
+++ b/wchat/common/HttpClient.php
@@ -332,7 +332,7 @@ class HttpClient
 	 * @return bool|string
 	 * @throws Exception
 	 */
-	private function matchHost($_= '')
+	private function matchHost($_string= '')
 	{
 		if (empty($_string)) {
 			return false;