为了执行此操作并强制浏览器将数据下载为文件,您必须将 mime 类型从 data:image 更改为 data:application/octet-stream。您需要创建自己的html2canvas 转换并手动处理onrendered 事件。然后在 onrendered 事件处理函数中,存储画布数据 url。之后,使用正则表达式将 base64 数据 mime 类型从 data:image 更改为 data:application/octet-stream。然后你可以使用window.open(uri)强制浏览器下载文件,但是如果你想指定一个文件名,你需要创建一个锚链接元素并用你想要的文件名设置下载属性:
HTML:
<table id="preview-table">
<tr>
<th>Company</th>
<th>Contact</th>
<th>Country</th>
</tr>
<tr>
<td>Alfreds Futterkiste</td>
<td>Maria Anders</td>
<td>Germany</td>
</tr>
<tr>
<td>Centro comercial Moctezuma</td>
<td>Francisco Chang</td>
<td>Mexico</td>
</tr>
<tr>
<td>Ernst Handel</td>
<td>Roland Mendel</td>
<td>Austria</td>
</tr>
<tr>
<td>Island Trading</td>
<td>Helen Bennett</td>
<td>UK</td>
</tr>
<tr>
<td>Laughing Bacchus Winecellars</td>
<td>Yoshi Tannamuri</td>
<td>Canada</td>
</tr>
<tr>
<td>Magazzini Alimentari Riuniti</td>
<td>Giovanni Rovelli</td>
<td>Italy</td>
</tr>
</table>
<button id="export">Table Export</button>
CSS:
table {
font-family: arial, sans-serif;
border-collapse: collapse;
width: 100%;
}
td, th {
border: 1px solid #dddddd;
text-align: left;
padding: 8px;
}
tr:nth-child(even) {
background-color: #dddddd;
}
Javascript:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script src="tableExport.jquery.plugin/html2canvas.js"></script>
<script type="text/javascript">
$('#export').on('click', function() {
html2canvas($('#preview-table'), {
onrendered: function(canvas) {
var saveAs = function(uri, filename) {
var link = document.createElement('a');
if (typeof link.download === 'string') {
document.body.appendChild(link); // Firefox requires the link to be in the body
link.download = filename;
link.href = uri;
link.click();
document.body.removeChild(link); // remove the link when done
} else {
location.replace(uri);
}
};
var img = canvas.toDataURL("image/png"),
uri = img.replace(/^data:image\/[^;]/, 'data:application/octet-stream');
saveAs(uri, 'tableExport.png');
}
});
});
</script>
在这里您可以找到一个工作示例:http://zikro.gr/dbg/html/tableExport/
Check Rob W's answer on Browser/HTML Force download of image from src=“data:image/jpeg;base64…” 和 Reddy's answer on Save file Javascript with file name [duplicate]