Import an Excel File data to Datagrid in WPF

I am trying to import an excel file to a datagrid in WPF. What I've found around the Internet won't rally do the trick.

I have a code that opens and reads excelfiles and outputs the data cells to a messagebox. I want to do so but to DataGrid instead. Here follows the code that needs to be changed:

private void ReadFromFile_Click(object sender, RoutedEventArgs e)
    {
        //Create COM Objects. Create a COM object for everything that is referenced
        Excel.Application xlApp = new Excel.Application();
        Excel.Workbook xlWorkbook = xlApp.Workbooks.Open(@"C:\Temp\vitoshacademy.xlsx");
        Excel._Worksheet xlWorksheet = xlWorkbook.Sheets[1];
        Excel.Range xlRange = xlWorksheet.UsedRange;

        int rowCount = xlRange.Rows.Count;
        int colCount = xlRange.Columns.Count;

        //iterate over the rows and columns and print to the console as it appears in the file
        //excel is not zero based!!
        for (int i = 1; i <= rowCount; i++)
        {
            for (int j = 1; j <= colCount; j++)
            {
                //new line
                if (j == 1)
                    MessageBox.Show("\r\n");

                //write the value to the console
                if (xlRange.Cells[i, j] != null && xlRange.Cells[i, j].Value2 != null)
                    MessageBox.Show(xlRange.Cells[i, j].Value2.ToString() + "\t");
            }
        }

        //cleanup
        GC.Collect();
        GC.WaitForPendingFinalizers();

        //rule of thumb for releasing com objects:
        //  never use two dots, all COM objects must be referenced and released individually
        //  ex: [somthing].[something].[something] is bad

        //release com objects to fully kill excel process from running in the background
        Marshal.ReleaseComObject(xlRange);
        Marshal.ReleaseComObject(xlWorksheet);

        //close and release
        xlWorkbook.Close();
        Marshal.ReleaseComObject(xlWorkbook);

        //quit and release
        xlApp.Quit();
        Marshal.ReleaseComObject(xlApp);


    }