你可以用它来保存文本和其他数据:
function downloadFile(name, data) {
let a = document.createElement("a");
if (typeof a.download !== "undefined") a.download = name;
a.href = URL.createObjectURL(new Blob([data], {
type: "application/octet-stream"
}));
a.dispatchEvent(new MouseEvent("click"));
}
这个函数将创建一个Anchor元素,通过.download(如果支持的话)设置名称,分配一个从对象(url . createobjecturl)创建的url (.href),在本例中是一个Blob对象,并分派一个单击事件。简而言之:就好像你在点击一个下载链接。
示例代码
downloadFile("textfile.txt", "A simple text file");
downloadFile(
"circle.svg",
`<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100">
<circle cx="50" cy="50" r="42" />
</svg>`
);
downloadFile(
"utf8string.txt",
new Uint8Array([85, 84, 70, 45, 56, 32, 115, 116, 114, 105, 110, 103]) // "UTF-8 string"
);
这个函数也接受File, Blob和MediaSource:
function downloadFile(name, data) {
if (!(data instanceof File || data instanceof Blob || data instanceof MediaSource)) {
return downloadFile(name, new Blob([data], {
type: "application/octet-stream"
}));
}
let a = document.createElement("a");
if (typeof a.download !== "undefined") a.download = name;
a.href = URL.createObjectURL(data);
a.dispatchEvent(new MouseEvent("click"));
}
或者你可以使用两个函数:
function downloadFile(name, data) {
return downloadObject(new Blob([data], {
type: "application/octet-stream"
}));
}
function downloadObject(name, object) {
let a = document.createElement("a");
if (typeof a.download !== "undefined") a.download = name;
a.href = URL.createObjectURL(object);
a.dispatchEvent(new MouseEvent("click"));
}