public void TestReplaceContentType()
{
Stream is1 = OpenXml4NetTestDataSamples.OpenSampleStream("sample.xlsx");
OPCPackage p = OPCPackage.Open(is1);
ContentTypeManager mgr = GetContentTypeManager(p);
Assert.True(mgr.IsContentTypeRegister("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml"));
Assert.False(mgr.IsContentTypeRegister("application/vnd.ms-excel.sheet.macroEnabled.main+xml"));
Assert.True(
p.ReplaceContentType(
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml",
"application/vnd.ms-excel.sheet.macroEnabled.main+xml")
);
Assert.False(mgr.IsContentTypeRegister("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml"));
Assert.True(mgr.IsContentTypeRegister("application/vnd.ms-excel.sheet.macroEnabled.main+xml"));
}