Returns the media type (
MIME
) of the file represented by a
File
对象。
var name = file.type;
A string, containing the media type(MIME) indicating the type of the file, for example "image/png" for PNG images
<input type="file" multiple onchange="showType(this)">
function showType(fileInput) {
var files = fileInput.files;
for (var i = 0; i < files.length; i++) {
var name = files[i].name;
var type = files[i].type;
alert("Filename: " + name + " , Type: " + type);
}
}
注意：
Based on the current implementation, browsers won't actually read the bytestream of a file to determine its media type. It is assumed based on the file extension; a PNG image file renamed to .txt would give "
text/plain
" and not "
image/png
". Moreover,
file.type
is generally reliable only for common file types like images, HTML documents, audio and video. Uncommon file extensions would return an empty string. Client configuration (for instance, the Windows Registry) may result in unexpected values even for common types.
Developers are advised not to rely on this property as a sole validation scheme.
| 规范 | 状态 | 注释 |
|---|---|---|
|
文件 API
The definition of 'type' in that specification. |
工作草案 | 初始定义。 |
| 桌面 | 移动 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
type
|
Chrome 13 | Edge 12 | Firefox 3.6 | IE 10 | Opera 16 | Safari Yes | WebView Android Yes | Chrome Android Yes | Firefox Android No | Opera Android No | Safari iOS Yes | Samsung Internet Android Yes |
完整支持
不支持
File