Question

<script>
function validate(){
u=document.CustomerLogin.UserName.value;
p=document.CustomerLogin.Password.value;
rp=document.CustomerLogin.RePassword.value;

if (u==""){
 document.write("Enter a unique username");
 return false;
 }
if (p!=rp){
 document.write("Retype Password Incorrect");
 return false;
 }
return true;
}
</script>

信件印在单独的页面上, 但是我要在文本框前的同一个地方打印! 请帮助。谢谢!

Answer 1

永远不要使用文档写入, 它很危险...

文档“getEplementById”(“硫丹元素化于该页面”) 。 InnerHTML = “用 javascript 添加的字符串 ” ;

<script>
function validate(){
u=document.CustomerLogin.UserName.value;
p=document.CustomerLogin.Password.value;
rp=document.CustomerLogin.RePassword.value;

if (u==""){
  document.getElementById("theIdOfyourTextBlocInForm").innerHTML = "Enter a unique username";
 return false;
 }
if (p!=rp){
 document.getElementById("theIdOfyourTextBlocInForm").innerHTML = "Retype Password Incorrect";
 return false;
 }
return true;
}
</script>

Answer 2

文档. write 将仅将信件附加到页面的末尾。最简单的解决方案是将其更改为这样的提醒 :

if (u==""){
 alert("Enter a unique username");
 return false;
}

否则您需要创建新的 DOM 元素( 手头之前或发现错误时), 以保持信件并放置在输入处旁边

Answer 3

您需要检测到文本更改。一种方法是使用 :

<input name="blah" onchange="validate()" ... />

EDIT To add text on the same page, include the script using <script src=...> and then add <div id= validation[i] ></div> next to each of the inputs where [i] is increased by 1 each time (so validation1 validation2 so on). Then, use getElementById( validation[i] ).innerHtml to change the value.

友情链接