private function _writeExternsheet($sheetname)
	{
		$record      = 0x0017;                     // Record identifier
		$length      = 0x02 + strlen($sheetname);  // Number of bytes to follow

		$cch         = strlen($sheetname);         // Length of sheet name
		$rgch        = 0x03;                       // Filename encoding

		$header      = pack("vv",  $record, $length);
		$data        = pack("CC", $cch, $rgch);
		$this->_append($header . $data . $sheetname);
	}
private function _writeExternsheet($sheetname)
	{
		$record      = 0x0017;                     // Record identifier
		$length      = 0x02 + strlen($sheetname);  // Number of bytes to follow

		$cch         = strlen($sheetname);         // Length of sheet name
		$rgch        = 0x03;                       // Filename encoding

		$header      = pack("vv",  $record, $length);
		$data        = pack("CC", $cch, $rgch);
		$this->_append($header . $data . $sheetname);
	}
private function _writeExternsheet ( $ sheetname ) { $ record = 0x0017 ; // Record identifier $ length = 0x02 + strlen ( $ sheetname ) ; // Number of bytes to follow $ cch = strlen ( $ sheetname ) ; // Length of sheet name $ rgch = 0x03 ; // Filename encoding $ header = pack ( "vv" , $ record , $ length ) ; $ data = pack ( "CC" , $ cch , $ rgch ) ; $ this -> _append ( $ header . $ data . $ sheetname ) ; }
Writes the Excel BIFF EXTERNSHEET record. These references are used by
formulas. NAME record is required to define the print area and the repeat
rows and columns.

A similar method is used in Worksheet.php for a slightly different purpose.

@param string $sheetname Worksheet name
Writes the Excel BIFF EXTERNSHEET record . These references are used by formulas . NAME record is required to define the print area and the repeat rows and columns .