使用javascript函数验证HTML表单复选框

Question

I am trying to validate a checkbox in a HTML form through a javascript function. I have been able to get the form to return false if left unchecked, but I cannot get the form to submit when the box is checked. What am I doing wrong?

Thank you for your time.

<form method="get" action="http://www.randyconnolly.com/tests/process.php" id="mainForm" onsubmit="return Validate()">

<div id="rectangle"> 
           <label>I accept the software license</label>
           <input id="accept" type="checkbox" name="accept" class="required">
        </div>

function Validate() {
//Form Validate
var t = document.getElementById("title").value;
if (t == "") {
    alert("Empty Title Field");
    document.getElementById("title").style.backgroundColor = "red";
}else{
    document.getElementById("title").style.backgroundColor = "white";
}

var d = document.getElementById("description").value;
if (d == "") {
    alert("Empty description field");
    document.getElementById("description").style.backgroundColor = "red";
}else{
    document.getElementById("description").style.backgroundColor = "white";
}

var c = document.getElementById("accept");
if (c.checked != "true") {
    alert("Please accept license");
    document.getElementById("rectangle").style.backgroundColor = "red";
    return false;
}else{
    document.getElementById("accept").style.backgroundColor = "white";
}

}

Answer 1

This will work if you change your checked logic slightly. You'll want to compare against boolean true instead of string "true"

if (c.checked != true) {
    alert("Please accept license");
    document.getElementById("rectangle").style.backgroundColor = "red";
    return false;
}else{
    document.getElementById("rectangle").style.backgroundColor = "white";
}

edit: I changed the element id passed in the else block so that it would correctly set #rectangle background to white.