Determine if window was opened by window.showModalDialog?

Does anyone know how to figure out if a window was opened by window.showModalDialog()? window.opener returns the parent window when the new window is opened by window.open(), but for some reason when you use window.showModalDialog(), windo开发者_JAVA百科w.opener returns as undefined. jQuery solutions are also welcome.

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You can check if window.dialogArguments is defined:

function isModalWindow()
{
    return (window.dialogArguments != null);
}