Multiple Worksheets, Borders, and Images

Few months back I was searching for the php code that creates excel file, which has got the content in multiple worksheet. I couldn't get any help from the net. Today just going through the PEAR Modules, I came across this script. This script generates excel file with multiple worksheets.

<?php
require_once 'Spreadsheet/Excel/Writer.php';
$workbook = new Spreadsheet_Excel_Writer(\"example4.xls\");
$worksheet =& $workbook->addWorksheet();\n
$worksheet->writeNote(1, 0, \"Invoice For New Customer 1\");
$worksheet->setRow(0, 50);
//$worksheet->insertBitmap(0, 0, \"logo.bmp\", 0, 0);
$left =& $workbook->addFormat(array(\"Left\" => 2));
$right =& $workbook->addFormat(array(\"Right\" => 2));
$number =& $workbook->addFormat(array(\"NumFormat\" =>'$####.00'));
$worksheet->write(1, 1, \"Client Name:Shakeel Shrestha\");
$worksheet->write(2, 1, \"Tax:\");
$worksheet->writeNumber(2, 2, .16);
$cart = array(\"Monitor\" => 12, \"Printer\" => 14.4);
$top = 4;
foreach ($cart as $item => $price){
$worksheet->write($top, 1, $item, $number);
$worksheet->write($top, 2, $price, $number);
$cell = \"C\" . ($top + 1);
$worksheet->writeFormula($top, 3, \"=($cell*C3)+$cell\",$number);
$top++;
}
$lastrow = $top + 1;
for ($i=1; $i <= $lastrow; $i++){
$worksheet->writeBlank($i, 0, $left);
$worksheet->writeBlank($i, 7, $right);
}
$worksheet->write($lastrow, 2, \"Total:\");
$worksheet->writeFormula($lastrow, 3, \"=SUM(D5:D$lastrow)\",$number);

//-----------------------------------------------------------------------------------------------------------
$worksheet1= & $workbook->addWorksheet();
$worksheet1->writeNote(1, 0, \"Invoice For New Customer 2\");
$worksheet1->setRow(0, 50);
//$worksheet->insertBitmap(0, 0, \"logo.bmp\", 0, 0);
$left =& $workbook->addFormat(array(\"Left\" => 2));
$right =& $workbook->addFormat(array(\"Right\" => 2));
$number =& $workbook->addFormat(array(\"NumFormat\" =>'$####.00'));
$worksheet1->write(1, 1, \"Client Name:Shajal Shrestha\");
$worksheet1->write(2, 1, \"Tax:\");
$worksheet1->writeNumber(2, 2, .16);
$cart = array(\"Monitor\" => 12, \"Printer\" => 14.4);
$top = 4;
foreach ($cart as $item => $price){
$worksheet1->write($top, 1, $item, $number);
$worksheet1->write($top, 2, $price, $number);
$cell = \"C\" . ($top + 1);
$worksheet1->writeFormula($top, 3, \"=($cell*C3)+$cell\",$number);
$top++;
}
$lastrow = $top + 1;
for ($i=1; $i <= $lastrow; $i++){ \n$worksheet1->writeBlank($i, 0, $left);
$worksheet1->writeBlank($i, 7, $right);
}
$worksheet1->write($lastrow, 2, \"Total:\");
$worksheet1->writeFormula($lastrow, 3, \"=SUM(D5:D$lastrow)\",$number);
$workbook->close();

?>