Help: About js problem_html/css_WEB-ITnose

Use JS to write a function for uploading images. How to use ?

Reply to discussion (solution)

Writing in JS, do you want it to be asynchronous?

Well,
I only use the FileUpload control to write, and now I want to use the html control to implement the image upload function

<img  src=""/〉<input type="file"/><input type="button" value="上传图片" onclick="upload()"/>

When you click to upload an image, save it in the specified file. And determine whether it is an image format. If it does not prompt an error message, after the upload is successful, img will display the uploaded photo
How to write this upload? Or is there any other method

Backend
Request.Files["file1"].SaveAs()

in IE It is different from the styles on Google and Firefox. Please pay attention to the compatibility of the browser when using it.

This is not what js can do.