1 files changed, 20 insertions, 0 deletions
diff --git a/file.go b/file.go
index 6a48c0c..4a2ab10 100644
--- a/file.go
+++ b/file.go
@@ -110,6 +110,26 @@ func (f *File) WriteToBuffer() (*bytes.Buffer, error) {
 	f.sharedStringsWriter()
 	f.styleSheetWriter()
 
+	for path, stream := range f.streams {
+		fi, err := zw.Create(path)
+		if err != nil {
+			zw.Close()
+			return buf, err
+		}
+		var from io.Reader
+		from, err = stream.rawData.Reader()
+		if err != nil {
+			stream.rawData.Close()
+			return buf, err
+		}
+		_, err = io.Copy(fi, from)
+		if err != nil {
+			zw.Close()
+			return buf, err
+		}
+		stream.rawData.Close()
+	}
+
 	for path, content := range f.XLSX {
 		fi, err := zw.Create(path)
 		if err != nil {