当页面以HTML加载时，如何指定应预先选择 元素？
使用checked属性可以指定要在页面加载时预先选择的<input>元素。该属性适用于-
<input type = "checkbox"> <input type = "radio">.
示例
您可以尝试运行以下代码以在HTML中实现选中的属性-
<!DOCTYPE html>
<html>
<body>
<p>Which sports do you like?</p>
<form action = "" method = "get">
<input type = "checkbox" name = "vehicle" value = "football" checked> Football<br>
<input type = "checkbox" name = "vehicle" value = "cricket" checked> Cricket<br>
<input type = "checkbox" name = "vehicle" value = "hockey"> Hockey<br>
<input type = "submit" value = "Submit">
</form>
</body>
</html>