def robotsrulesetOfDomain(self, domain):
		'''检查domain是否在数据库中,
			否 --> (False, None)
			是 --> (True, 数据库中存储的robots.txt内容)
		'''
		exist = False
		cur = self.conn.cursor()
		# 是否存在
		cur.execute("SELECT 1 FROM Domains WHERE domain=?", (domain,))
		if cur.fetchone() :
			exist = True
		# 存在的话,结果是什么
		cur.execute("SELECT rules FROM Domains,Rulesets "
			"WHERE domain=? AND Domains.did=Rulesets.did"
			,(domain,) )
		ruleset = cur.fetchone()
		return (exist, ruleset)
def draw(self, context):
        layout = self.layout

        layout.operator(
                "wm.url_open", text="Add-ons Catalog", icon='URL',
                ).url = "http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts"

        layout.separator()

        layout.operator(
                "wm.url_open", text="How to share your add-on", icon='URL',
                ).url = "http://wiki.blender.org/index.php/Dev:Py/Sharing"
        layout.operator(
                "wm.url_open", text="Add-on Guidelines", icon='URL',
                ).url = "http://wiki.blender.org/index.php/Dev:2.5/Py/Scripts/Guidelines/Addons"
        layout.operator(
                "wm.url_open", text="API Concepts", icon='URL',
                ).url = bpy.types.WM_OT_doc_view._prefix + "/info_quickstart.html"
        layout.operator("wm.url_open", text="Add-on Tutorial", icon='URL',
                ).url = "http://www.blender.org/api/blender_python_api_current/info_tutorial_addon.html"