diff --git a/wchat/common/HttpClient.php b/wchat/common/HttpClient.php
index f00de0f..fa456b8 100644
--- a/wchat/common/HttpClient.php
+++ b/wchat/common/HttpClient.php
@@ -334,7 +334,7 @@ class HttpClient
 	 */
 	private function matchHost($_string = '')
 	{
-		if (empty($string)) {
+		if (empty($_string)) {
 			return false;
 		}