生成随机字符串

php：

#!/usr/bin/php
<?php
function str_rand($length = 11, $char = ‘0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ‘) {
     if(!is_int($length) || $length < 0) {
         return false;
     }
      $string = ‘‘;
     for($i = $length; $i > 0; $i--) {
         $string .= $char[mt_rand(0, strlen($char) - 1)];
     }
     return $string;
}
for($i=0;$i<10;$i++){
    $str = str_rand();
    file_put_contents("test123.txt","$str\n",FILE_APPEND);
}

shell：

#!/bin/bash
randstr() {
        index=0
        str=""
        for i in {A..Z}
        do
                arr[index]=$i
                index=`expr ${index} + 1`
        done
        for i in {0..9}
        do
                arr[index]=$i
                index=`expr ${index} + 1`
        done
        for i in {1..11}
        do
                str="$str${arr[$RANDOM%$index]}"
        done
        echo $str
}

for i in {0..5000}
do
        echo `randstr` >>test.csv
done

生成随机字符串

原文：http://blog.51cto.com/8588192/2336119