如何使用交替的字母和数字生成随机的6个字符的字符串？

Question

I have a code in PHP that is able to generate a 6-character alpha-numeric string but it does not ensure that there are 3 letters and 3 numbers generated.

It generates a string such as "ps7ycn" It does not have 3 numbers in between the alphabet. The numbers should be in between the letters.

example : a3g5h9

Answer 1

Here's one way you could address this:

$alpha  = 'abcdefghijklmnopqrstuvwxyz';
$number = '0123456789';

$random = '';

for ( $i = 0; $i < 6; ++$i ) {
    if ( $i % 2 ) {
        $random .= substr( $number, rand( 0, strlen( $number ) - 1 ), 1 );
    } else {
        $random .= substr( $alpha, rand( 0, strlen( $alpha ) - 1 ), 1 );
    }
}

$random will now contain a six-character random value with the first, third, and fifth characters coming from $alpha and second, fourth, and sixth characters coming from $number.