Fix issue #24: remove invalid characters in worksheet names

src/xlsx/xlsxutility.cpp

@@ -177,4 +177,30 @@ QString xl_rowcol_to_cell_fast(int row, int col)
     return col_str + QString::number(row);
 }
 
+/*
+  Creates a valid sheet name
+    minimum length is 1
+    maximum length is 31
+    doesn't contain special chars: / \ ? * ] [ :
+    Sheet names must not begin or end with ' (apostrophe)
+
+  Invalid characters are replaced by one space character ' '.
+ */
+QString createSafeSheetName(const QString &nameProposal)
+{
+    if (nameProposal.isEmpty())
+        return QString();
+
+    QString ret = nameProposal;
+    if (nameProposal.contains(QRegularExpression(QStringLiteral("[/\\\\?*\\][:]+"))))
+        ret.replace(QRegularExpression(QStringLiteral("[/\\\\?*\\][:]+")), QStringLiteral(" "));
+    while(ret.contains(QRegularExpression(QStringLiteral("^\\s*'\\s*|\\s*'\\s*$"))))
+        ret.remove(QRegularExpression(QStringLiteral("^\\s*'\\s*|\\s*'\\s*$")));
+    ret = ret.trimmed();
+    if (ret.size() > 31)
+        ret = ret.left(31);
+    return ret;
+}
+
+
 } //namespace QXlsx

src/xlsx/xlsxutility_p.h

@@ -60,5 +60,7 @@ XLSX_AUTOTEST_EXPORT int xl_col_name_to_value(const QString &col_str);
 XLSX_AUTOTEST_EXPORT QString xl_rowcol_to_cell(int row, int col, bool row_abs=false, bool col_abs=false);
 XLSX_AUTOTEST_EXPORT QString xl_rowcol_to_cell_fast(int row, int col);
 
+XLSX_AUTOTEST_EXPORT QString createSafeSheetName(const QString &nameProposal);
+
 } //QXlsx
 #endif // XLSXUTILITY_H

src/xlsx/xlsxworkbook.cpp

@@ -205,10 +205,10 @@ Worksheet *Workbook::addWorksheet(const QString &name, int sheetId)
 Worksheet *Workbook::insertWorkSheet(int index, const QString &name)
 {
     Q_D(Workbook);
-    QString worksheetName = name;
-    if (!name.isEmpty()) {
+    QString worksheetName = createSafeSheetName(name);
+    if (!worksheetName.isEmpty()) {
         //If user given an already in-used name, we should not continue any more!
-        if (d->worksheetNames.contains(name))
+        if (d->worksheetNames.contains(worksheetName))
             return 0;
     } else {
         do {