From 873e6f7a0bc94a1292be556a671decf9f6427aa1 Mon Sep 17 00:00:00 2001
From: Ladel <infobox12@mail.ru>
Date: Sun, 8 Nov 2015 01:46:34 +0500
Subject: [PATCH] Multi-row head export

---
 js/buttons.flash.js      | 14 ++++++++++++--
 js/buttons.html5.js      | 28 ++++++++++++++++++++--------
 js/buttons.print.js      |  6 +++++-
 js/dataTables.buttons.js | 15 +++++++++++----
 4 files changed, 48 insertions(+), 15 deletions(-)

diff --git a/js/buttons.flash.js b/js/buttons.flash.js
index 4adb74f9..6cc15148 100644
--- a/js/buttons.flash.js
+++ b/js/buttons.flash.js
@@ -590,7 +590,15 @@ var _exportData = function ( dt, config )
 		return s;
 	};
 
-	var header = config.header ? join( data.header )+newLine : '';
+	if (config.header) {
+		var header = [];
+		for ( var i=0, ien=data.header.length ; i<ien ; i++ ) {
+			header.push( join( data.header[i] ) );
+		}
+		header.join( newLine );
+	} else {
+		var header = '';
+	}
 	var footer = config.footer ? newLine+join( data.footer ) : '';
 	var body = [];
 
@@ -765,7 +773,9 @@ DataTable.ext.buttons.excelFlash = $.extend( {}, flashButton, {
 		};
 
 		if ( config.header ) {
-			xml += addRow( data.header );
+			for ( var i=0, ien=data.header.length ; i<ien ; i++ ) {
+				xml += addRow( data.header[i] );
+			}
 		}
 
 		for ( var i=0, ien=data.body.length ; i<ien ; i++ ) {
diff --git a/js/buttons.html5.js b/js/buttons.html5.js
index b890b5d4..34b42f00 100644
--- a/js/buttons.html5.js
+++ b/js/buttons.html5.js
@@ -366,7 +366,15 @@ var _exportData = function ( dt, config )
 		return s;
 	};
 
-	var header = config.header ? join( data.header )+newLine : '';
+	if (config.header) {
+		var header = [];
+		for ( var i=0, ien=data.header.length ; i<ien ; i++ ) {
+			header.push( join( data.header[i] ) );
+		}
+		header.join( newLine );
+	} else {
+		var header = '';
+	}
 	var footer = config.footer ? newLine+join( data.footer ) : '';
 	var body = [];
 
@@ -639,7 +647,9 @@ DataTable.ext.buttons.excelHtml5 = {
 		};
 
 		if ( config.header ) {
-			xml += addRow( data.header );
+			for ( var i=0, ien=data.header.length ; i<ien ; i++ ) {
+				xml += addRow( data.header[i] );
+			}
 		}
 
 		for ( var i=0, ien=data.body.length ; i<ien ; i++ ) {
@@ -699,12 +709,14 @@ DataTable.ext.buttons.pdfHtml5 = {
 		var rows = [];
 
 		if ( config.header ) {
-			rows.push( $.map( data.header, function ( d ) {
-				return {
-					text: typeof d === 'string' ? d : d+'',
-					style: 'tableHeader'
-				};
-			} ) );
+			for ( var i=0, ien=data.header.length ; i<ien ; i++ ) {
+				rows.push( $.map( data.header[i], function ( d ) {
+					return {
+						text: typeof d === 'string' ? d : d+'',
+						style: 'tableHeader'
+					};
+				} ) );
+			}
 		}
 
 		for ( var i=0, ien=data.body.length ; i<ien ; i++ ) {
diff --git a/js/buttons.print.js b/js/buttons.print.js
index d824bb2d..978bbce0 100644
--- a/js/buttons.print.js
+++ b/js/buttons.print.js
@@ -90,7 +90,11 @@ DataTable.ext.buttons.print = {
 		var html = '<table class="'+dt.table().node().className+'">';
 
 		if ( config.header ) {
-			html += '<thead>'+ addRow( data.header, 'th' ) +'</thead>';
+            html += '<thead>';
+            for ( var i=0, ien=data.header.length ; i<ien ; i++ ) {
+                html += addRow( data.header[i], 'th' );
+            }
+            html += '</thead>';
 		}
 
 		html += '<tbody>';
diff --git a/js/dataTables.buttons.js b/js/dataTables.buttons.js
index 36610f6d..e1ca227d 100644
--- a/js/dataTables.buttons.js
+++ b/js/dataTables.buttons.js
@@ -1523,10 +1523,17 @@ var _exportData = function ( dt, inOpts )
 		return str;
 	};
 
+	var headCells = dt.table().context[0].aoHeader;
+	var header = new Array( headCells.length );
+	for ( var i=0, ien=headCells.length ; i<ien ; i++ ) {
+		var rowHead = new Array( headCells[i].length );
 
-	var header = dt.columns( config.columns ).indexes().map( function (idx, i) {
-		return config.format.header( dt.column( idx ).header().innerHTML, idx );
-	} ).toArray();
+		for ( var j=0 ; j<headCells[i].length ; j++ ) {
+			rowHead[j] = config.format.header( headCells[i][j].cell.innerText, j, i );
+		}
+
+		header[i] = rowHead;
+	}
 
 	var footer = dt.table().footer() ?
 		dt.columns( config.columns ).indexes().map( function (idx, i) {
@@ -1540,7 +1547,7 @@ var _exportData = function ( dt, inOpts )
 		.cells( rowIndexes, config.columns )
 		.render( config.orthogonal )
 		.toArray();
-	var columns = header.length;
+	var columns = header[0].length;
 	var rows = columns > 0 ? cells.length / columns : 0;
 	var body = new Array( rows );
 	var cellCounter = 0;