Unable to open the frame in the same page

I am using frame This is my code so far for middlereports.php:

<frameset cols="21%,79%,0%" frameborder="0" framespacing="5" border="0">
  <frame src="reportstree.php" id="frTree" name="frTree">
  <frame src="generatereportdetails.php" id="frDesc" name="frDesc">
  <frame src="UntitledFrame-3" name="frHidden" id="frHidden">
</frameset>

now I am calling this page Here in my topui.php

<?php
{
    echo "<a href=\"middlereports.php\" target=\"frMiddle\">";
}
?>

I want to开发者_如何学编程 open this page in same window in topui.php but i m unable to do that

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There is no target frMiddle in your frameset. Did you mean frDesc?

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Why don't you use an iframe instead?