LinqToExcel: Distinct values in excel column

Question

This might be a very simple thing for you gurus, but I'm not familiar with C#4 and INTEROP. Therefore, I'm stumped. Here's my problem. I have a excel column that has duplicate data and I want to trim it down to only unique values. Here's what the data looks like: ``` ColA ColB 10 Adam 12 Jane 14 Adam 18 Adam 20 Eve ``` So, in the end I just want unique names from ColB: ``` Adam Jane Eve ``` I know that I can do this by getting all those values into a List and then adding the Distinct functionality to it. But I think I'm doing something wrong. Anyway, here's my program: ``` Application XLApp = new Microsoft.Office.Interop.Excel.Application(); var XLBook = XLApp.Workbooks.Open(@"c:	emp\Test.xls", ReadOnly: false); // Grab the 1st sheet var XLSheet = (Microsoft.Office.Interop.Excel.Worksheet)XLBook.Worksheets.get_Item(1); XLApp.Visible = true; // I think I need help with the following lines IEnumerable<string> myCol = XLApp.Range["B2", XLApp.Range["B2"].End[XlDirection.xlDown]].Select()…

Accepted Answer

You can use LinqToExcel to easily get the distinct values in a column

```
var excel = new ExcelQueryFactory("worksheetFileName");
var distinctNames = (from row in excel.WorkSheet()
                     select row["ColB"]).Distinct()
```

EDIT:

To use `Distinct` in LinqToExcel, you have to use a class that corresponds to the row data.

```
public class WorksheetRow
{
    public string ColA { get; set; }
    public string ColB { get; set; }
}

var excel = new ExcelQueryFactory("worksheetFileName");
var distinctNames = (from row in excel.WorkSheet<WorksheetRow>()
                     select row.ColB).Distinct()
```

LinqToExcel: Distinct values in excel column

Solution

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