我的目标是向用户提供有关输入错误的信息。在这个例子中，我可以在没有角度的情况下做到这一点。我还设法使用“innerHTML”属性重新创建了以下示例，但它也不适用于 NVDA，简而言之，它只是在发生错误时将一个节点附加到正文
<!DOCTYPE html>
<html><head>
<meta http-equiv="content-type" content="text/html; charset=windows-1252">
<title>Contact form (WAI-ARIA)</title>
<script type="text/javascript">
function removeOldAlert()
{
var oldAlert = document.getElementById("alert");
if (oldAlert)
document.getElementById("error").removeChild(oldAlert);
}
function addAlert(aMsg)
{
removeOldAlert();
var newAlert = document.createElement("div");
newAlert.setAttribute("role", "alert");
newAlert.setAttribute("id", "alert");
var msg = document.createTextNode(aMsg);
newAlert.appendChild(msg);
document.getElementById("error").appendChild(newAlert);
}
function checkEntryValidity(aID, aSearchTerm, aMsg)
{
var elem = document.getElementById(aID);
var invalid = (elem.value.indexOf(aSearchTerm) < 0);
if (invalid) {
elem.setAttribute("aria-invalid", "true");
addAlert(aMsg);
} else {
elem.setAttribute("aria-invalid", "false");
removeOldAlert();
}
}
</script>
</head>
<body>
<form method="post" action="post.php">
<fieldset><legend>Please …