PHP sha1是什么意思?
PHP sha1() 函数
定义和用法
sha1() 函数计算字符串的 SHA-1 散列。
sha1() 函数使用美国 Secure Hash 算法 1。
如果成功,则返回所计算的 SHA-1 散列,如果失败,则返回 false。
语法
sha1(string,raw)
参数
string 必需。规定要计算的字符串。
raw
可选。规定十六进制或二进制输出格式:
TRUE - 原始 20 字符二进制格式
FALSE - 默认。40 字符十六进制数
注释:该参数是 PHP 5.0 中添加的。
例子
例子 1
<?php $str = 'Hello'; echo sha1($str); ?>
输出:
f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0
例子 2
在本例中,我们将输出 sha1() 的结果,然后对其测试:
<?php $str = 'Hello'; echo sha1($str); if (sha1($str) == 'f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0') { echo "<br />Hello world!"; exit; } ?>
输出:
f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0 Hello world!
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