Q1753 How do you determine if a variable exists?

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Q1753 How do you determine if a variable exists?

Simply test if the window object has a property by the same name:

<script language="JavaScript"><!--
if (window.myVariableName) {
  alert('variable exists');
}
else {
  alert('either variable exits or its value is null or false');
}
//--></script>

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• 13:47:41 5/01/01 Alex Vincent