POST适用于警报消息，但并非没有警报消息

Question

I am making a post request to google app script with the code below

    var url ="MY WEBAPP EXEC"

     function submitForm() {
        var postRequest = {}
        postRequest.name = $("#inputName").val();
        postRequest.email = $("#inputEmail1").val();
        postRequest.message = $("#inputMessage").val();

        alert(JSON.stringify(postRequest));  // this alert

        $.post(url, postRequest, function(data,status){
           alert('success')
        });
    }

I am very confused why the post is working with the alert but doesn't work without it. Thank you.

=== OK I guess my question was not clear enough sorry.

I have a form accessing GAS remotely. I assumed the url implied that I was accessing GAS remotely. At the moment I am working on my localhost and on my JS above it works if the alert statement is present and does not do anything if alert is not there.

I was watching the execution list on GSuite Developer Hub to see if the request failed or completed. I observed if the alert statement is in the script the execution status is completed but if the alert statement is not there nothing happens. I assume that my post script is not working if alert is not there. Any idea why?

Answer 1

You haven't shown exactly how that function is called, but it's likely to be because, if this is truly a "form submit" action, the result of submitting a form is to "load a new page" (which can be the same page you're on, and is so by default with no action attribute in the form tag

Since you want to perform AJAX on form submit, you need to "prevent" the "default" form submit action - this can be achieved as shown in the second and third lines below

 var url ="MY WEBAPP EXEC"
 function submitForm(e) { // if this function is called using an event handler, it gets an event as the first and only argument
    e.preventDefault(); // prevent the "default" form submit action
    var postRequest = {}
    postRequest.name = $("#inputName").val();
    postRequest.email = $("#inputEmail1").val();
    postRequest.message = $("#inputMessage").val();

    alert(JSON.stringify(postRequest));  // this alert

    $.post(url, postRequest, function(data,status){
       alert('success')
    });
}