That definitely on to something there. I was able to reproduce it myself. It has to do with the Table you created. if you open your file and remove it using the "Convert To Range" option in the Table Tools tab the problem goes away.
I looked at the source code and it extracts the xml files at the zip level and didnt see any indication that it was actually messing with them - seemed to be a straight copy.
Very strange because if we create and save the xlsx file including a table from EPPlus the problem is not there. This works just fine:
[TestMethod]
public void Template_Copy_Test()
{
//http://stackoverflow.com/questions/28722945/epplus-with-a-template-is-not-working-as-expected
const string templatePath = "c:\\temp\\testtemplate.xlsx"; // the path of the template
const string resultPath = "c:\\temp\\result.xlsx"; // the path of our result
//Throw in some data
var dtdata = new DataTable("tblData");
dtdata.Columns.Add(new DataColumn("Col1", typeof(string)));
dtdata.Columns.Add(new DataColumn("Col2", typeof(int)));
dtdata.Columns.Add(new DataColumn("Col3", typeof(int)));
for (var i = 0; i < 20; i++)
{
var row = dtdata.NewRow();
row["Col1"] = "String Data " + i;
row["Col2"] = i * 10;
row["Col3"] = i * 100;
dtdata.Rows.Add(row);
}
var templateFile = new FileInfo(templatePath);
if (templateFile.Exists)
templateFile.Delete();
using (var pck = new ExcelPackage(templateFile))
{
var ws = pck.Workbook.Worksheets.Add("Data");
ws.Cells["A1"].LoadFromDataTable(dtdata, true);
for (var i = 2; i <= dtdata.Rows.Count + 1; i++)
ws.Cells[i, 4].Formula = String.Format("{0}*{1}", ExcelCellBase.GetAddress(i, 2), ExcelCellBase.GetAddress(i, 3));
ws.Tables.Add(ws.Cells[1, 1, dtdata.Rows.Count + 1, 4], "TestTable");
pck.Save();
}
using (var pck = new ExcelPackage(new FileInfo(resultPath), templateFile)) // creating a package with the given template, and our result as the new stream
{
// note that I am not doing any work ...
pck.Save(); // savin our work
}
}
BUT.....
If we open testtemplate.xlsx
, remove the table, save/close the file, reopen, and reinsert the exact same table the problem shows up when you run this:
[TestMethod]
public void Template_Copy_Test2()
{
//http://stackoverflow.com/questions/28722945/epplus-with-a-template-is-not-working-as-expected
const string templatePath = "c:\\temp\\testtemplate.xlsx"; // the path of the template
const string resultPath = "c:\\temp\\result.xlsx"; // the path of our result
var templateFile = new FileInfo(templatePath);
using (var pck = new ExcelPackage(new FileInfo(resultPath), templateFile)) // creating a package with the given template, and our result as the new stream
{
// note that I am not doing any work ...
pck.Save(); // savin our work
}
}
It has to be something burried in their zip copy methods but I nothing jumped out at me.
But at least you can see about working around it.
Ernie