PHP Large File Reading Techniques

To read data from large files, you can use PHP’s fread function to read file content chunk by chunk instead of loading the entire file into memory at once.

Here is an example code:

$filename = 'path/to/large/file.txt';
$chunkSize = 1024; // 每次读取的块大小（字节）

$handle = fopen($filename, 'r');
if ($handle) {
    while (!feof($handle)) {
        $data = fread($handle, $chunkSize);
        // 处理读取的数据，例如打印到控制台
        echo $data;
    }
    fclose($handle);
}

The above code will open a file handle, then use the fread function to read the file content in chunks within a loop for processing. The feof function is used to check if the file has been completely read, if not, it continues to loop and read the next chunk of data. Finally, the file handle is closed.

Please note that depending on your needs, you may need to adjust the size of each block read according to the actual situation. A block size that is too small may result in frequent file read and write operations, while a block size that is too large may consume too much memory.

Additionally, if you only need to read a portion of the file data, you can use the fseek function to move the file pointer to the desired position, and then start using the fread function to read the data.