IE5中用JavaScript跨frame加option問題

跨frame加option，以下代碼在IE5中會出錯，但在IE4、IE6、Opera6、NNx中都沒有問題：

<script>
function addOption(aSelect, optionId, optionName) {
    newOption = new Option(optionName, optionId);
    aSelect.options[aSelect.options.length] = newOption;
}
</script>
      

這樣才是對的：

<script>
function addOption(aSelect, optionId, optionName) {
    ownerWindow = aSelect.document.parentWindow;
    ownerWindow.newOption = new Option(optionName, optionId);
    aSelect.options[aSelect.options.length] = ownerWindow.newOption;
}

function crossFrameAddOption() {
    var aSelect = parent.otherFrameName.document.forms[0].theSelectName;
    addOption(aSelect , "id"+ aSelect.options.length, "name"+ aSelect.options.length);
}
</script>
<input type="button" onClick="crossFrameAddOption();" value="test">
      

微軟的解釋如下： In general, at least in the older browser versions, performance seems to improve if you call methods on the target frame if they are stored there as well. This is particularly relevant when trying to add options to a select box in another frame. Make sure you create the option in that other frame so you are adding it to a local select box, instead of trying to cross frame boundaries.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnwebteam/html/Webteam02052002.asp