选择文件后立即POST-POSTimmediatelyafterselectafile

36  

To submit it immediately, just do this:

要立即提交，请执行以下操作：

If you are using JQuery:

如果您使用的是JQuery：

$("input[name='file_1']").change(function() { this.form.submit(); });

About your other questions:

关于您的其他问题：

1) There are many methods out there... for example:

1）有很多方法......例如：

http://valums.com/ajax-upload/

http://valums.com/ajax-upload/

http://www.webtoolkit.info/ajax-file-upload.html

http://www.webtoolkit.info/ajax-file-upload.html

(and many more. Just google for: "Ajax file upload" or "iframe file upload")

（以及更多。仅谷歌：“Ajax文件上传”或“iframe文件上传”）

2) Don't worry about the width of the field. As you don't know how long can it be the path, it would never be long enough (i think). Also browsers may display it very different. For example Safari or Chrome show it very different from Firefox or IE. Just use the default length or the one that looks better with your design.

2）不要担心场地的宽度。因为你不知道这条路有多长，所以它永远不够长（我想）。浏览器也可能显示它非常不同。例如，Safari或Chrome显示它与Firefox或IE非常不同。只需使用默认长度或与您的设计看起来更好的长度。

2  

For the first one:

对于第一个：

I'm not sure about making the field wide enough though. Sometimes CSS is crippled on file upload fields to prevent exploits.

我不确定这个领域是否足够广阔。有时CSS在文件上载字段中被削弱以防止漏洞利用。

0  

Rough guess at what you want - when the text field changes it will trigger the form submission

粗略猜测你想要什么 - 当文本字段改变时它将触发表单提交

$('.target').change(function() {
  document.forms["myform"].submit();
});

Edit: Sorry, I've used jQuery...

编辑：对不起，我用过jQuery ...

If you submit the form onchange, you won't notice the field get populated and therefore should not need to change the text length. If you desire to, I would get the character count of the string in the field and then apply a size attribute to the input

如果您提交表格onchange，您将不会注意到该字段已填充，因此不需要更改文本长度。如果你愿意，我会在字段中获得字符串的字符数，然后将size属性应用于输入

mylength = document.getElementById('myfield').value
document.getElementById('myfield').size = mylength;

0  

In case you don't want or need to submit the whole form on file input select, then you can do this to send only the file:

如果您不想或不需要在文件输入选择上提交整个表单，那么您可以这样做只发送文件：

$(document).ready(function (e) {
	$("#uploadImage").on('change',(function(e) {
		// append file input to form data
		var fileInput = document.getElementById('uploadImage');
		var file = fileInput.files[0];
		var formData = new FormData();
		formData.append('uploadImage', file);

		$.ajax({
			url: "ajaxupload.php",
			type: "POST",
			data: formData,
			contentType: false,
			cache: false,
			processData:false,
			success: function(data) {
				if(data=='invalid') {
					// invalid file format.
					$("#err").html("Invalid File !").fadeIn();
				}

				else {
					// view uploaded file.
					$("#preview").html(data).fadeIn();
					$("#form")[0].reset();
				}
			},
			error: function(e) {
				$("#err").html(e).fadeIn();
			}
		});
	}));
});

So first you get the input file element with getElementById(), then you append to FormData, then send the FormData as data in your ajax call. Do the server side upload processing in ajaxupload.php.

首先，您使用getElementById（）获取输入文件元素，然后附加到FormData，然后将FormData作为数据发送到ajax调用中。在ajaxupload.php中进行服务器端上传处理。