ajax请求返回状态= 0，提交事件，但使用状态=200作为keyup事件。

I am having a problem with the following javascript/ajax code. The code searches a JSON file which just has some contact names and email addresses in it. When the "keyup" event calls addr.search everything is fine and in the function call to ajaxCall the attributes request.readyState=4 and request.Status=200, but when the "submit" event calls the same search calling the same addr.search function the request.status is 0 and it fails.I am having a problem with the following javasc