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crypt(const char *key, const char *salt) function is one of the C language functions and returns a string encrypted using DES, Blowfish or MD5. This function behaves differently on different operating systems, and some operating systems support more than one algorithm type. At installation time, PHP checks what algorithms are available and what algorithms are used.
This article mainly introduces PHP to use crypt() function for encryption in detail. It has certain reference value. Interested friends can refer to it
1. Code
<?php $str = '应用crypt()函数进行单向加密!'; //声明字符串变量$str echo '加密前$str的值为：'.$str; $crypttostr = crypt($str); //对变量$str加密 echo '<p>加密后$str的值为：'.$crypttostr; //输出加密后的变量 ?>
2. Running result
The parameter does not contain salt, The ciphertext obtained by encryption is different every time.
The value of $str before encryption is: apply the crypt() function for one-way encryption!
The value of $str after encryption is: $1$Re4.Gg4.$D.yd00xX0fFfIfp6KrKGN0
3. Code
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>使用crypt函数进行数据验证</title>
<style type="text/css">
<!--
body,td,th {
font-size: 12px;
}
body {
margin-left: 10px;
margin-top: 10px;
margin-right: 10px;
margin-bottom: 10px;
}
.STYLE1 {
font-size: 14px;
font-weight: bold;
}
-->
</style>
</head>
<body>
<p align="center">
<?php
$conn = mysql_connect("localhost","root","root") or die("数据库链接错误".mysql_error());
mysql_select_db("db_database21",$conn) or die("数据库访问错误".mysql_error());
mysql_query("set names gb2312");
?>
</p>
<table width="777" height="587" border="0" align="center" cellpadding="0" cellspacing="0" background="images/bg.jpg">
<tr>
<td width="149" height="200"> </td>
<td width="448"> </td>
<td width="158"> </td>
</tr>
<tr>
<td height="187"> </td>
<td align="center" valign="middle"> <form id="form1" name="form1" method="post" action="index.php">
<table height="129" border="0" cellpadding="0" cellspacing="0">
<tr>
<td width="100" height="30" align="right" valign="middle" scope="col"><span class="STYLE1">用户名：</span></td>
<td width="100" height="30" align="left" valign="middle" scope="col"><label for="textfield"></label>
<input name="username" type="text" id="username" size="24" /></td>
<td width="100" align="center" valign="middle" scope="col"> </td>
</tr>
<tr>
<td height="30" align="right" valign="middle" class="STYLE1" scope="col">密码：</td>
<td height="30" align="left" valign="middle" scope="col"><input name="password" type="password" id="password" size="25" /></td>
<td align="center" valign="middle" scope="col"> </td>
</tr>
<tr>
<td height="40" colspan="3" align="center" valign="middle" scope="col"><input type="image" name="imageField" src="images/bg2.JPG" />
<input type="image" name="imageField2" src="images/bg1.JPG" onclick="form.reset();return false;" /></td>
</tr>
</table>
</form>
<?php
if(trim($_POST[username])!= "" and trim($_POST[password])!= ""){
$usr = crypt(trim($_POST[username]),$_POST[username]);
$pwd = crypt(trim($_POST[password]),$_POST[password]);
$sql = "select * from tb_user where username = '".$usr."' and password='".$pwd."'";
$rst = mysql_query($sql,$conn);
$result=mysql_num_rows($rst);
if($result>0){
echo "<font color='red'>用户登录成功。</font>";
}else{
echo "<font color='green'>用户登录失败!</font>";
}
}else{
echo "请认真填写用户名和密码！";
}
?></td>
<td> </td>
</tr>
<tr>
<td height="200"> </td>
<td> </td>
<td> </td>
</tr>
</table>
</body>
</html>
4. Running results
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