How to solve the problem of garbled characters when php generates UTF-8 encoded CSV files and opens them with Excel

Reason: There is no BOM in the output CSV file.

What is BOM?

There is a character called "ZERO WIDTH NO-BREAK SPACE" in UCS encoding, and its encoding is FEFF. FFFE is a character that does not exist in UCS, so it should not appear in actual transmission. The UCS specification recommends that we transmit the characters "ZERO WIDTH NO-BREAK SPACE" before transmitting the byte stream. In this way, if the receiver receives FEFF, it indicates that the byte stream is Big-Endian; if it receives FFFE, it indicates that the byte stream is Little-Endian. Therefore, the character "ZERO WIDTH NO-BREAK SPACE" is also called BOM.

UTF-8 does not require a BOM to indicate the byte order, but can use the BOM to indicate the encoding method. The UTF-8 encoding of the character "ZERO WIDTH NO-BREAK SPACE" is EF BB BF. So if the receiver receives a byte stream starting with EF BB BF, it knows that it is UTF-8 encoded.

Windows uses BOM to mark the encoding method of text files.

How to output BOM in PHP?

Before everything is output

print(chr(0xEF).chr(0xBB).chr(0xBF));

Sample code:

<?php
    function writeCsvToFile($file,array $data){
        $fp = fopen($file, &#39;w&#39;);
        //Windows下使用BOM来标记文本文件的编码方式
        fwrite($fp,chr(0xEF).chr(0xBB).chr(0xBF));
        foreach ($data as $line) {
            fputcsv($fp, $line);
        }
        fclose($fp);
    }