How to pass fileReader.readAsBinaryString?

Question

Node.js

Hello,
I am transferring binaryString from the client to the server, but it seems that the encoding is recognized differently on the server, for example, after reader.readAsBinaryString on the client it will be PK???!?bîh^?????[Content_Types].xml
and on the server already
âÁ(Ú+þº ö "C b ¶v¯vµ3µW^ oBBëÌ$Q·ªU ס?jë¬ÀÂÉåVÛõ½ì
although in the vscode debugger the encoding is recognized correctly.
It also works correctly with the text, but with the contents of the file there
is nothing. What goes wrong. ..

Answer 1

const file = e.target.files[0];
const ab = await file.arrayBuffer();
WebSocket.send(ab);
const workbook = XLSX.read(ab, {
    type: "buffer"
});