我的目标是向用户提供有关输入错误的信息。通过这个例子，我可以做到这一点而没有角度。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 enter your contact details</legend>
<label for="name">Your name (required):</label>
<input name="name" id="name" aria-required="true" onblur="checkEntryValidity('name', ' ', 'Invalid name entered!');" aria-invalid="true" value=""><br>
<label for="email">E-Mail address (required):</label>
<input name="email" id="email" aria-required="true" onblur="checkEntryValidity('email', '@', 'Invalid e-mail address');" aria-invalid="true" value=""><br>
<label for="website">Website (optional):</label>
<input name="website" id="website" value="">
</fieldset>
<label for="message">Please enter your message (required):</label><br>
<textarea name="message" id="message" rows="5" cols="80" aria-required="true"></textarea><br>
<input name="submit" value="Send message" type="submit">
<input name="reset" value="Reset form" type="reset">
</form>
<div id="error"></div>
</body></html>
（警告输入的名称无效！）
但 NVDA 会忽略此类警报消息
<!-- widget with model binding here -->
<div role="alert" class="validation" *ngIf="model.hasErrors()">
<div *ngFor="let message of model.errors">{{message}}</div>
</div>
我不知道为什么 NVDA 不注册该内容更改。
角2
我正在使用 Windows 10、Firefox 50.1.0 和 NVDA 2016.4。