my purpose is user enter only email or mobile number.i have the partial success in that.code notify user in OR logic but....

IF user entered the incorrect mobile & email @same time then user must be notified for dat.

    var emailReg = /^([\w-\.]+@([\w-]+\.)+[\w-]{2,4})?$/;
    var emailaddressVal = $("#UserEmail").val();

   ////email & mobile input cheak

   if(emailaddressVal == '' && $("#mobile").val() == '') {
              $("#UserEmail").after('<p><span class="error">Please enter your email address.</span></p>')
              $("#mobile").after('<p><span class="error">Please enter your Mobile number.</span></p>')

              hasError = true;
    }

  //////validating currect email
   else if(!emailReg.test(emailaddressVal)) {
              $("#UserEmail").after('<p><span class="error">Enter a valid email address.</span></p>')   

              hasError = true;

    } 
  //////Mobile number
   else if( $("#mobile").val()) {
             $("#mobile").after('<p><span class="error">Enter currect Mobile number.</span></p>')

             hasError = true;
    }