从base64字符串获取文件名

Question

我有base64解码的文件如下：

"data:application/vnd.openxmlformats-officedocument.wordprocessingml.document;base64,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…"

就是这个文件：

是否有任何简单的方法可以仅使用 javascript 从

file name

字符串中获取

base64

？

Answer 1

嗯，不...base64 字符串不包含文件名，只包含文件的内容。

如果您想保留文件名，则必须以其他方式存储它。它已经在您向我们展示的文件对象上可用，您只需根据您的用例以合理的方式存储它即可。

Answer 2

在 JS 中，您可以执行正则表达式来从 Base64 字符串中获取文件名。

const regex = /filename:([^,]+\.csv)/;
const str = "data:text/csv;base64,TmFtZSxBZ2UsQnJlZWQsQ29sb3IKQnVkZHksMyxHb2xkZW4gUmV0cmlldmVyLEdvbGRlbgpNYXgsNSxHZXJtYW4gU2hlcGhlcmQsQmxhY2sgYW5kIFRhbgpCYWlsZXksMixMYWJyYWRvciBSZXRyaWV2ZXIsQ2hvY29sYXRlCkx1Y3ksNCxCZWFnbGUsVHJpLWNvbG9yCkNoYXJsaWUsNixQb29kbGUsV2hpdGUKRGFpc3ksMSxCdWxsZG9nLEJyb3duIGFuZCBXaGl0ZQpDb29wZXIsNyxTaWJlcmlhbiBIdXNreSxHcmF5IGFuZCBXaGl0ZQpNb2xseSw0LERhY2hzaHVuZCxSZWQKUm9ja3ksMixCb3hlcixGYXduCkJlbGxhLDUsWW9ya3NoaXJlIFRlcnJpZXIsQmxhY2sgYW5kIFRhbg==,filename:dogs.csv";
const match = str.match(regex);

if (match) {
    console.log(match[0]); // This will output: filename:dogs.csv
}