php64大小的base64_encode字符串 - 文件

Question

我想知道如何知道base64_encoded字符串的文件大小？例如:

$data = 'iVBORw0KGgoAAAANSUhEUgAAABwAAAASCAMAAAB/2U7WAAAABl'
       . 'BMVEUAAAD///+l2Z/dAAAASUlEQVR4XqWQUQoAIAxC2/0vXZDr'
       . 'EX4IJTRkb7lobNUStXsB0jIXIAMSsQnWlsV+wULF4Avk9fLq2r'
       . '8a5HSE35Q3eO2XP1A1wQkZSgETvDtKdQAAAABJRU5ErkJggg==';
$data = base64_decode($data);

谢谢

Answer 1

strlen(base64_decode($encoded_data));

并且作为一个粗略的经验法则,base64编码将原始数据的大小增加了大约33%

Answer 2

如果你想知道大小而不解码,我相信以下工作:

$size = (int) (strlen(rtrim($data, '=')) * 3 / 4);

要么:

$size = (strlen($data) * 3 / 4) - substr_count(substr($data, -2), '=');

否则,只需strlen()按照建议使用解码数据作为Marc.

Answer 3

试试这个，也给你字节、KB 和 MB 的大小..

public function getBase64ImageSize($base64Image){ //return memory size in B, KB, MB
    try{
        $size_in_bytes = (int) (strlen(rtrim($base64Image, '=')) * 3 / 4);
        $size_in_kb    = $size_in_bytes / 1024;
        $size_in_mb    = $size_in_kb / 1024;

        return $size_in_mb;
    }
    catch(Exception $e){
        return $e;
    }
}