Timely question: http://aspnet.4guysfromrolla.com/articles/021104-1.aspx

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This probably does what you need:

http://www.metabuilders.com/Tools/DialogWindow.aspx

I'd agree you should go with the MetaBuilders deal if that does what you need.

I've worked with a function that sets form fields on the window.opener form, which is essentially what the Metabuilders control does. Here's a simple function that does this:

function SetImageId(imageID,imageSrc) {
var i, inp = self.location.search.substr(1);
var queryString = new Object();
if (inp.length > 0) {
var ary = inp.replace(/\+/g, " ").split("&");
for (i in ary) {
ary[i] = unescape(ary[i]).split("=");
queryString[ary[i][0]] = ary[i][1];
}
}

var form = queryString["formname"];
var field = queryString["fieldname"];
var field2 = queryString["imagename"];
var srcString = 'uploads/images/' + imageSrc;

eval("window.opener.document." + form + "." + field + ".value='" + imageID + "';");
eval("window.opener.document." + form + "." + field2 + ".src='" + srcString + "';");
window.close();
}

Is the question "how to do this" or "is this the right thing to do" ?

dgdgdgd