added param_alphanumext - a-zA-Z0-9_-.

htdocs/lib/web.php

@@ -578,6 +578,36 @@ function param_alphanum($name) {
     throw new ParameterException("Parameter '$name' = '$value' is not an alphanum");
 }
 
+/**
+ * This function returns a GET or POST parameter as an alphanumeric string with optional
+ * default.  If the default isn't specified and the parameter hasn't been sent,
+ * a ParameterException exception is thrown. Likewise, if the parameter isn't a
+ * valid alpha string, a ParameterException exception is thrown
+ *
+ * Valid characters are a-z and A-Z and 0-9 and _ and - and .
+ *
+ * @param string The GET or POST parameter you want returned
+ * @param mixed [optional] the default value for this parameter
+ *
+ * @return string The value of the parameter
+ *
+ */
+function param_alphanumext($name) {
+    $args = func_get_args();
+
+    list ($value, $defaultused) = call_user_func_array('_param_retrieve', $args);
+
+    if ($defaultused) {
+        return $value;
+    }
+
+    if (preg_match('/^[a-zA-Z0-9_.-]+$/',$value)) {
+        return $value;
+    }
+
+    throw new ParameterException("Parameter '$name' = '$value' is not an alphanumext");
+}
+
 /**
  * This function returns a GET or POST parameter as an array of integers with optional
  * default.  If the default isn't specified and the parameter hasn't been sent,