Why does the page refresh when sending an ajax request?

<code><button class="btn btn-default" onclick="set_chat_msg()">send</button></code>

Click the button to trigger the function

set_chat_msg() part:

<code>var url= "chat_send_ajax.php";
url += "?name=" + strname + "&msg=" + strmsg;//将用户名和消息变量拼接进url中
oxmlHttpSend.open("GET",url,true);//打开请求
oxmlHttpSend.send(null);//发送
//alert(oxmlHttpSend);//为什么在firefox下不注释这里php就无法接收到数据执行呢？chrome是正常的</code>

Then php receives it and processes it.

Why does the page refresh once after I click the button? Then if php cannot receive data at all and will not execute it under firefox, chrome can.

Reply content:

<code><button class="btn btn-default" onclick="set_chat_msg()">send</button></code>

Click the button to trigger the function

set_chat_msg() part:

<code>var url= "chat_send_ajax.php";
url += "?name=" + strname + "&msg=" + strmsg;//将用户名和消息变量拼接进url中
oxmlHttpSend.open("GET",url,true);//打开请求
oxmlHttpSend.send(null);//发送
//alert(oxmlHttpSend);//为什么在firefox下不注释这里php就无法接收到数据执行呢？chrome是正常的</code>

Then php receives it and processes it.

Why does the page refresh once when I click the button? Then if php cannot receive data at all and will not execute it under firefox, chrome can.

As long as you are in the <form> tag, you must clearly specify the type of <button>. Remember to add type="button" or type="submit" to <button> , I’ll be in tears if I talk too much~

Please add the type='button' attribute to the button tag, because the browser will by default think that the attribute of the button is submit.type='submit', and the default behavior of submitting the form will occur.

<code><button type='button' class="btn btn-default" onclick="set_chat_msg()">send</button></code>

W3shool:

Always specify the type attribute for buttons. The default type in Internet Explorer is "button", while the default in other browsers (including the W3C specification) is "submit".