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IsNumeric

Checks if a string is a numeric value. If AllowFloat is true then the string may contain a floating point number, otherwise it must be an integer. If TrimWhiteSpace is True any white space surrounding Value is trimmed before testing.

function IsNumeric(Value: string; const AllowFloat: Boolean;
  const TrimWhiteSpace: Boolean = True): Boolean;
var
  ValueInt: Int64;      // dummy integer value
  ValueFloat: Extended; // dummy float value
begin
  if TrimWhiteSpace then
    Value := SysUtils.Trim(Value);
  // Check for valid integer
  Result := SysUtils.TryStrToInt64(Value, ValueInt);
  if not Result and AllowFloat then
    // Wasn't valid as integer, try float
    Result := SysUtils.TryStrToFloat(Value, ValueFloat);
end;

Kind of Snippet: Routine

Required units: SysUtils.

Required snippets: None.

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