Adding a row to a google spreadsheet
There's a line missing in the example in the documentation:
ListEntry row = new ListEntry();
row.Elements.Add(new ListEntry.Custom() { LocalName = "firstname", Value = "Joe" });
row.Elements.Add(new ListEntry.Custom() { LocalName = "lastname", Value = "Smith" });
row.Elements.Add(new ListEntry.Custom() { LocalName = "age", Value = "26" });
row.Elements.Add(new ListEntry.Custom() { LocalName = "height", Value = "176" });
If you switch to the Java view, you can see that the Java version includes this line.