diff --git a/main.cpp b/main.cpp
index b4f236e..d51b7e7 100644
--- a/main.cpp
+++ b/main.cpp
@@ -2637,4 +2637,41 @@ GValue phpgtk_get_gvalue(Php::Value phpgtk_value, GType type_column)
 
     return gtk_value;
 
+}
+
+
+
+void phpgtk_throw_wrong_type(int param, Php::Type type)
+{
+    char *buffer;
+    int len;
+    std::string str_type;
+
+    switch(type) {
+        case Php::Type::Undefined: str_type.assign("undefined"); break;
+        case Php::Type::Null: str_type.assign("Null"); break;
+        case Php::Type::False: str_type.assign("False"); break;
+        case Php::Type::True: str_type.assign("True"); break;
+        case Php::Type::Numeric: str_type.assign("Numeric"); break;
+        case Php::Type::Float: str_type.assign("Float"); break;
+        case Php::Type::String: str_type.assign("String"); break;
+        case Php::Type::Array: str_type.assign("Array"); break;
+        case Php::Type::Object: str_type.assign("Object"); break;
+        case Php::Type::Resource: str_type.assign("Resource"); break;
+        case Php::Type::Reference: str_type.assign("Reference"); break;
+        case Php::Type::Constant: str_type.assign("Constant"); break;
+        case Php::Type::ConstantAST: str_type.assign("ConstantAST"); break;
+        case Php::Type::Bool: str_type.assign("Bool"); break;
+        case Php::Type::Callable: str_type.assign("Callable"); break;
+    }
+    
+    // Get len of string
+    len = snprintf(NULL, 0, "expects at least %d parameters, %s given", param, str_type.c_str());
+    buffer = (char *)malloc((len + 1) * sizeof(char));
+    
+    // Save into buffer
+    snprintf(buffer, len+1, "expects at least %d parameters, %s given", param, str_type.c_str());
+
+    // throw
+    throw Php::Exception(buffer);
 }
\ No newline at end of file
diff --git a/main.h b/main.h
index 1e0da0f..20ecd9f 100644
--- a/main.h
+++ b/main.h
@@ -1,10 +1,12 @@
-#ifndef _PHPGTK_H_
-#define _PHPGTK_H_
+#ifndef _PHPGTK_MAIN_H_
+#define _PHPGTK_MAIN_H_
 
     #include <phpcpp.h>
     #include <iostream>
     #include <gtk/gtk.h>
 
+    #include "php-gtk.h"
+
     #include "src/GObject.h"
 
     #include "src/Gdk.h"
@@ -189,5 +191,6 @@
     
 
     GValue phpgtk_get_gvalue(Php::Value phpgtk_value, GType type_column);
+    void phpgtk_throw_wrong_type(int param, Php::Type type);
 
 #endif
\ No newline at end of file
diff --git a/php-gtk.cpp b/php-gtk.cpp
new file mode 100644
index 0000000..4b1ee21
--- /dev/null
+++ b/php-gtk.cpp
@@ -0,0 +1,16 @@
+
+#include "php-gtk.h"
+
+bool phpgtk_check_parameter(Php::Value value, Php::Type expected_type, bool required)
+{
+	Php::call("var_dump", "OK1");
+	if(required) {
+		Php::call("var_dump", "OK2");
+		if(value.type() == Php::Type::Null) {
+			Php::call("var_dump", "OK3");
+			throw Php::Exception("tipo errado");
+		}
+		Php::call("var_dump", "OK4");
+	}
+
+}
\ No newline at end of file
diff --git a/php-gtk.h b/php-gtk.h
new file mode 100644
index 0000000..882ce7f
--- /dev/null
+++ b/php-gtk.h
@@ -0,0 +1,12 @@
+#ifndef _PHPGTK_H_
+#define _PHPGTK_H_
+
+    #include <phpcpp.h>
+    #include <iostream>
+    #include <gtk/gtk.h>
+
+
+	bool phpgtk_check_parameter(Php::Value value, Php::Type expected_type, bool required);
+
+
+#endif
\ No newline at end of file
diff --git a/src/GtkBox.cpp b/src/GtkBox.cpp
index 72ff3d5..24bfd11 100644
--- a/src/GtkBox.cpp
+++ b/src/GtkBox.cpp
@@ -13,6 +13,8 @@ GtkBox_::~GtkBox_() = default;
 
 void GtkBox_::__construct(Php::Parameters &parameters)
 {
+	//phpgtk_check_parameter(parameters[0], Php::Type::Numeric, TRUE);
+
 	int int_child = (int)parameters[0];
 	GtkOrientation child = (GtkOrientation)int_child;
 
diff --git a/src/GtkBox.h b/src/GtkBox.h
index b69638a..8a11e40 100644
--- a/src/GtkBox.h
+++ b/src/GtkBox.h
@@ -5,7 +5,9 @@
     #include <phpcpp.h>
     #include <gtk/gtk.h>
 
-	#include "GtkContainer.h"
+    #include "../php-gtk.h"
+
+    #include "GtkContainer.h"
 	#include "GtkWidget.h"
 	#include "GtkPackType.h"
 
diff --git a/test.php b/test.php
index 91d8734..7b2001a 100644
--- a/test.php
+++ b/test.php
@@ -94,11 +94,14 @@ function GtkCellRendererToggled($renderer=NULL, $path=NULL)
 
 // ----------------------
 // Vertical box
-$vbox = new GtkBox(GtkOrientation::VERTICAL);
+$vbox = new GtkBox();
+die("OK");
+
+// $vbox->pack_start(2.2, TRUE, TRUE);
 
 // ----------------------
 // Menu
-$vbox->pack_start($hlbl = new GtkLabel("- GtkMenuBar"), TRUE, TRUE, 1); $hlbl->set_xalign(0);
+$vbox->pack_start(2, TRUE, TRUE, 1); $hlbl->set_xalign(0);
 
 $menubar = new GtkMenuBar();
 $vbox->pack_start($menubar, FALSE, FALSE, 0);