使用 Ajax 提交表单，但获取"Illegal Invocation"

Question

我尝试通过ajax提交表单，下面是表单。

<form class="form-vertical" method="POST" id="request-form" action="/post_handler?request=add_data" enctype="multipart/form-data">
<div class="form-group">
<label for="date_inp" class="control-label">Date</label>
<input class="form-control hasDatepicker" id="datepicker" type="text" name="date">
</div>
</div>
<div class="form-group">
<label for="file_inp">Upload File</label>
<div>
<input class="form-control" id="file_inp" type="file" placeholder="Upload File" name="file">
</div>
</div>
<div class="form-group">
<div>
<button type="submit" class="btn btn-default submit-button" onclick="on_click_form_submit(event);">Submit</button>
</div>
</div>
</form>

这是点击功能。

on_click_form_submit = function(event) {
event.preventDefault();
var form_data = new FormData($('#request-form')[0]),
form_url = '/' + $('#request-form')[0].action.split('/').pop();
console.log('url: ' + form_url);
$.ajax({
url: form_url,
type: 'POST',
data: form_data,
dataType: 'json',
encode: true
})
.done(function(response) {
alert(response);
})
.fail(function(xhr, status, error) {
alert(xhr.responseText);
});
return false;
};

当我单击提交时，它会报告

Uncaught TypeError: Illegal invocation
at add (jquery-1.9.1.js:7340)
at buildParams (jquery-1.9.1.js:7392)
at Function.jQuery.param (jquery-1.9.1.js:7360)
at Function.ajax (jquery-1.9.1.js:7863)
at Object.on_click_form_submit (spa.shell.js:301)

Answer 1

根据文档，jQuery的$.ajax接受：

类型：普通对象或字符串或数组

因此，您的form_data应该采用这些格式之一 - 它不应该是FormData的实例化。这取决于后端的期望，但一种选择是将表单的值转换为具有serializeArray()的对象：

on_click_form_submit = function(event) {
event.preventDefault();
var form_data = $('#request-form').serializeArray(),
form_url = '/' + $('#request-form')[0].action.split('/').pop();
console.log('url: ' + form_url);
$.ajax({
url: form_url,
type: 'POST',
data: form_data,
dataType: 'json',
encode: true
})
.done(function(response) {
alert(response);
})
.fail(function(xhr, status, error) {
alert(xhr.responseText);
});
return false;
};

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form class="form-vertical" method="POST" id="request-form" action="/post_handler?request=add_data" enctype="multipart/form-data">
<div class="form-group">
<label for="date_inp" class="control-label">Date</label>
<input class="form-control hasDatepicker" id="datepicker" type="text" name="date">
</div>
</div>
<div class="form-group">
<label for="file_inp">Upload File</label>
<div>
<input class="form-control" id="file_inp" type="file" placeholder="Upload File" name="file">
</div>
</div>
<div class="form-group">
<div>
<button type="submit" class="btn btn-default submit-button" onclick="on_click_form_submit(event);">Submit</button>
</div>
</div>
</form>