1 <form name="form1" action=""> 2     密码:<input type="password" size="8" onkeyup="pwStrength(this.value)" onblur="pwStrength(this.value)"> 3     <br> 4     密码强度: 5     <table width="220px" border="1" cellspacing="0" cellpadding="1" bordercolor="#eeeeee" height="22px"> 6         <tr align="center" bgcolor="#f5f5f5"> 7             <td width="33%" id="strength_L">弱</td> 8             <td width="33%" id="strength_M">中</td> 9             <td width="33%" id="strength_H">强</td>10         </tr>11     </table>12 </form>

 1 function pwdStrength(pwd) { 2     O_color = "#eeeeee"; 3     L_color = "#FF0000"; 4     M_color = "#FF9900"; 5     H_color = "#33CC00"; 6     var level = 0, strength = "O"; 7     if (pwd == null || pwd == ‘‘) { 8         strength = "O"; 9         Lcolor = Mcolor = Hcolor = O_color;10     }11     else {12         var mode = 0;13         if (pwd.length <= 4)14             mode = 0;15         else {16             for (i = 0; i < pwd.length; i++) {17                 var charMode, charCode;18                 charCode = pwd.charCodeAt(i);19                 // 判断输入密码的类型20                 if (charCode >= 48 && charCode <= 57) //数字  21                     charMode = 1;22                 else if (charCode >= 65 && charCode <= 90) //大写  23                     charMode = 2;24                 else if (charCode >= 97 && charCode <= 122) //小写  25                     charMode = 4;26                 else27                     charMode = 8;28                 mode |= charMode;29             }30             // 计算密码模式31             level = 0;32             for (i = 0; i < 4; i++) {33                 if (mode & 1)34                     level++;35                 mode >>>= 1;36             }37         }38         switch (level) {39             case 0:40                 strength = "O";41                 Lcolor = Mcolor = Hcolor = O_color;42                 break;43             case 1:44                 strength = "L";45                 Lcolor = L_color;46                 Mcolor = Hcolor = O_color;47                 break;48             case 2:49                 strength = "M";50                 Lcolor = Mcolor = M_color;51                 Hcolor = O_color;52                 break;53             default:54                 strength = "H";55                 Lcolor = Mcolor = Hcolor = H_color;56                 break;57         }58     }59     document.getElementById("strength_L").style.background = Lcolor;60     document.getElementById("strength_M").style.background = Mcolor;61     document.getElementById("strength_H").style.background = Hcolor;62     return strength;63 }