How can I update the Version history in C#?

Question

In document library, I've some documents with version history. In C#, can I get all the version history of document and update the user?

The version history of a document is like below:

Data                Modified By

doc1 changed        User X
some text           User X

Now in C# can I update the Modified By user value with another user?

Thanks in advance

Answer 1

SPSite site = new SPSite("http://sharepointsite/subsite");
SPWeb web = site.OpenWeb();
SPList list = web.Lists["My List"];
web.AllowUnsafeUpdates = true;
foreach (SPListItem item in list.Items)
{
  item["Modified"] = "Set the date";
  item["Created"] = "Set the date";
  item["Editor"]="itemCreatedUser";
  item.UpdateOverwriteVersion();
}

Hope this helps!

Answer 2

If you call SPListItem.Update() in code I believe that changes the Modified By value to whichever user triggered the code (while SystemUpdate() does not).