javascript - 如何为HTML输入的文件设置值？(How to set a value to a file input in HTML?)

Question

Note:(注意：)

The answers & comments below reflect the state of legacy browsers in 2009. Now you can actually set the value of the file input element dynamically/programatically using JavaScript and a dataTransfer or FileList object in 2017.(下面的答案和评论反映了2009年旧版浏览器的状态。现在，您实际上可以在2017年使用JavaScript和dataTransfer或FileList对象动态/以编程方式设置文件输入元素的值。) See the answer in this question for details as well as a demo:(有关详细信息和演示，请参见此问题的答案：)
How to set file input value programatically (ie: when drag-dropping files)?(如何以编程方式设置文件输入值（即：拖放文件时）？)

How can I set the value of this?(如何设置此值？)

<input type="file" />   ask by Alon Gubkin translate from so

Answer 1

You cannot due to security reasons.(由于安全原因，您不能。)

Imagine:(想像：) <form name="foo" method="post" enctype="multipart/form-data"> <input type="file" value="c:/passwords.txt"> </form> <script>document.foo.submit();</script> You don't want the websites you visit to be able to do this, do you?(您不希望所访问的网站能够做到这一点，对吗？) =)(=）)