How to determine which radio button is selected
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I have a program where im displaying a map in an <iframe> tag. So far i have have two radio buttons set up but im not sure how the syntax would look to determine which one is selected. If i set the value to the link i want to go to what would the <iframe> look like?

Anything along the lines of this?

`<iframe src=radiobutton1.isChecked width="1200" height="750"></iframe>`