function Button_3_onClicked() {
if (getCustomProperty("Virus_Count") == 0) {
try {
window.alert("No virus is found yet, nothing to kill.");
} catch (err) {
window.alert('"No virus is found yet, nothing to kill."');
}
} else {
if (window.confirm("Kill all found viruses?")) {
try {
window.alert("Done!");
} catch (err) {
window.alert('"Done!"');
}
} else {

}
}
}
addHandler(document.getElementById("Button_3"), "click", Button_3_onClicked);