title: How to check TDateTime contents are valid
body: <p>Is there a way to check whether a Delphi <code>TDateTime</code> variable has valid contents without trapping exceptions on conversions?</p>
  
  <p>I have written an application that has to parse through hundreds of huge files written as raw Delphi records that contain a <code>TDateTime</code> field. Occasionally I get a record where the contents has a <code>TDateTime</code> value like <code>2.0927117954e+262</code> which gives a <code>Floating point invalid Operation</code> exception when passed to conversion routines. I know I can simply trap the exception but this is such a nuisance when debugging as the debugger keeps stopping and I want to keep it enabled in case of other errors.</p>