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| <script>
var sel =document.getElementById('sel');
sel.observes =[];
sel.attach =function (obj) {
sel.observes[sel.observes.length] = obj;
};
sel.detach = function (obj) {
for( var i=0; i < sel.observes.length; i++) {
if(this.observes[i] == obj) {
delete this.observes[i];
}
}
};
sel.onchange = sel.notify =function () {
for( var i=0; i < sel.observes.length; i++) {
//
this.observes[i].update(this);
}
};
var test2 = document.getElementById('test2');
var test3 = document.getElementById('test3');
test3.update = function (sel) {
if(sel.value == '1'){
this.innerHTML = '2';
} else if(sel.value == '0') {
this.innerHTML ='a';
}
};
test2.update = function (sel) {
if(sel.value == '1'){
this.innerHTML = '1';
} else if(sel.value == '0') {
this.innerHTML ='s';
}
};
sel.attach(test2);
sel.attach(test3);
</script>
|