防止在用戶輸入錯誤時重新加載頁面

Question

我創建這樣的注冊頁面

<form name='registration' action="registration.php" method="post" onSubmit="return formValidation();">
    FirstName:<input type = "Text" name = "firstname">
    <input type = "submit" name = "register" value="register">
</form>

這是我的javascript函數

function formValidation() {  
   var fn = document.registration.firstname;
   if ( fname_validation( fn ) ) {}
}

function fname_validation( fn ) {
   var fn_len = fn.value.length;
   var fn_char = /^[A-Za-z]+$/;
   if ( fn_len == 0 ) {
       alert("first name cannot empty");
       return false;
   }
   if ( !fn.value.match( fn_char ) ) {
       alert("first name must enter alphabet only");
       return false;
   } else {
       return true;
   }
}

注冊表格正在運行，但是如果用戶輸入了號碼，它將提醒並重新加載頁面，從而刷新頁面。 如果我想在用戶輸入錯誤時不刷新頁面以保持用戶輸入，該怎么辦？

Answer 1

在您的JavaScript中，您應該返回正確的值...

例：

function formValidation() {  
   var fn = document.registration.firstname;
   return fname_validation( fn );
}

Answer 2

在表單提交中添加return false

<form name='registration' action="registration.php" method="post" onSubmit="return formValidation();return false;">
    FirstName:<input type = "Text" name = "firstname">
    <input type = "submit" name = "register" value="register">
    </form>

Answer 3

為了防止表單提交，只需在formValidation（）函數中返回false