1document.getElementById("myCheckBoxID").checked = true; // Check
2document.getElementById("myCheckBoxID").checked = false;// Uncheck
3
1// Check
2document.getElementById("checkbox").checked = true;
3
4// Uncheck
5document.getElementById("checkbox").checked = false;
6
1document.getElementById("checkbox_id").checked;
2//If checked returns true;
3//else returns false;