javaScript 简单验证代码(用户名,密码,邮箱)

复制代码 代码如下:

  <script language="javascript">

  function IsDigit(cCheck)

  {

  return (('0'<=cCheck) && (cCheck<='9'));

  }

  function IsAlpha(cCheck)

  {

  return ((('a'<=cCheck) && (cCheck<='z')) || (('A'<=cCheck) && (cCheck<='Z')))

  }

  function IsaNull(cCheck)

  {

  return(cCheck != " ")

  }

  function checkform()

  {

  id = document.sform1.id.value;

  if (id == "")

  {

  alert("请输入注册名");

  document.sform1.id.focus();

  return false;

  }

  for (nIndex=0; nIndex<id.length; nIndex++)

  {

  cCheck = id.charAt(nIndex);

  if (!(IsDigit(cCheck) || IsAlpha(cCheck) || cCheck=='-' || cCheck=='_' || cCheck=='.'))

  {

  alert("用户名只能使用字母、数字以及-、_和.,并且不能使用中文");

  document.sform1.id.focus();

  return false;

  }

  }

  chineseid = document.sform1.chineseid.value;

  if (chineseid == "")

  {

  alert("请输入中文昵称");

  document.sform1.chineseid.focus();

  return false;

  }

  password = document.sform1.password.value;

  if (password == "")

  {

  alert("请输入登陆密码");

  document.sform1.password.focus();

  return false;

  }

  password1 = document.sform1.password1.value;

  if (password>password1)

  {

  alert("重复密码与登陆密码不相同");

  document.sform1.password.focus();

  document.sform1.password1.focus();

  return false;

  }

  if (password<password1)

  {

  alert("重复密码与登陆密码不相同");

  document.sform1.password.focus();

  document.sform1.password1.focus();

  return false;

  }

  if (document.sform1.email.value == "")

  {

  alert("请输入您的E-MAIL地址");

  document.sform1.email.focus();

  return false;

  }

  email=document.sform1.email.value;

  emailerr=0

  for (i=0; i<email.length; i++)

  {

  if ((email.charAt(i) == "@") & (email.length > 5))

  {

  emailerr=emailerr+1

  }

  }

  if (emailerr != 1)

  {

  alert("请输入正确的E-MAIL地址");

  document.sform1.email.focus();

  return false;

  }

  if (document.sform1.checkask.value=="")

  {

  alert("密码提示问题不能为空");

  document.sform1.checkask.focus();

  return false;

  }

  if (document.sform1.checkans.value=="")

  {

  alert("您的密码提示问题答案不能为空");

  document.sform1.checkans.focus();

  return false;

  }

  return true;

  }

  </script>