<!DOCTYPE html>
<html>
<head>
<script>
function check()
{
document.getElementById("check1").checked=true
}
function uncheck()
{
document.getElementById("check1").checked=false
}
function status()
{
var x=document.getElementById("check1").checked
if (x)
{
alert("I like summer.")
}
else
{
alert("I don't like summer.")
}
}
</script>
</head>
<body>
<form>
<input type="checkbox" id="check1">Do you like summer?
</form>
<button onclick="check()">Check Checkbox</button>
<button onclick="uncheck()">Uncheck Checkbox</button>
<button type="submit" onclick="status()">Submit</button>
</body>
</html>
