向 button 元素分配 onclick 事件：
<!DOCTYPE html> <html> <body> <p>点击按钮就可以执行 <em>displayDate()</em>函数。</p> <button onclick = "displayDate()">点击点击点击</button> <script> function displayDate() { document.getElementById("demo").innerHTML = Date(); } </script> <p id = "demo">会展示日期</p> </body> </html>
2.
<!DOCTYPE html>
<html>
<body onload = "checkCookies()">
<script>
function checkCookies()
{
try
{
if (navigator.cookieEnabled == true)
{
alert("已启用 cookie")
}
else
{
alert("未启用 cookie")
}
}
catch (err)
{
alert('asdf')
}
}
</script>
<p>提示框会告诉你，浏览器是否已启用 cookie。</p>
</body>
</html>
3.
<!DOCTYPE html> <html> <head> <script> function myF() { var x = document.getElementById("fname"); x.value = x.value.toUpperCase(); } </script> </head> <body> 请输入应为字符：<input type = "text" id = "fname" onchange = "myF()"> <p>当您离开输入字段时，会触发将输入文本转换为大写的函数。</p> </body> </html>