Avoiding error when using writeToStdOut/String with an empty document.

Created by: Dj1b

As writeToFile doesn’t create a temp file on empty document, resulting in an error, we assure to have at least one cell written for writeToStdOut and writeToString methods.

xlsxwriter.class.php

@@ -66,20 +66,24 @@ class XLSXWriter
 	public function writeToStdOut()
 	{
 		$temp_file = $this->tempFilename();
-		self::writeToFile($temp_file);
+		self::writeToFile($temp_file, true);
 		readfile($temp_file);
 	}
 
 	public function writeToString()
 	{
 		$temp_file = $this->tempFilename();
-		self::writeToFile($temp_file);
+		self::writeToFile($temp_file, true);
 		$string = file_get_contents($temp_file);
 		return $string;
 	}
 
-	public function writeToFile($filename)
+	public function writeToFile($filename, $forceCreateFile=false)
 	{
+        // Create an empty sheet on forceCreateFile
+	    if (empty($this->sheets) and $forceCreateFile)
+	        $this->writeSheetRow('Sheet1', array(''));
+
 		foreach($this->sheets as $sheet_name => $sheet) {
 			self::finalizeSheet($sheet_name);//making sure all footers have been written
 		}
@@ -116,6 +120,21 @@ class XLSXWriter
 		$zip->close();
 	}
 
+	public function writeToStdOutAsAttachment($filename)
+	{
+		if (!preg_match('/\.xlsx$/', $filename))
+			$filename .= '.xlsx';
+		$content = $this->writeToString();
+		header('Content-Disposition: attachment; filename='.$filename);
+		header('Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
+		header('Content-Length: '.strlen($content));
+		header('Content-Transfer-Encoding: binary');
+		header('Cache-Control: must-revalidate');
+		header('Pragma: public');
+		echo $content;
+		die();
+	}
+
 	protected function initializeSheet($sheet_name, $col_widths=array(), $auto_filter=false, $freeze_rows=false, $freeze_columns=false )
 	{
 		//if already initialized