C#

private void MyComboBox_TextChanged(object sender, EventArgs e)
{
   if(MyComboBox.Text == "Yes")
     {
       textBox1.Enabled = true;
     }
   else
     {
       textox1.Text = ""; //am setting the text box to null if there is any text in it.
       textbox1.Enabled = false;
     }
}

using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using Microsoft.Office.Tools.Ribbon; 
using System.Reflection; 
using Excel = Microsoft.Office.Interop.Excel; 
using Microsoft.Office.Core; 

private void btnImport_Click(object sender, RibbonControlEventArgs e) 
{ 

// Object for missing (or optional) arguments. 
object oMissing = System.Reflection.Missing.Value; 

// Create an instance of Microsoft Excel, make it visible, 
// and open Book1.xls. 
Excel.ApplicationClass oExcel = new Excel.ApplicationClass(); 
oExcel.Visible = true; 
Excel.Workbooks oBooks = oExcel.Workbooks; 
Excel._Workbook oBook = null; 
oBook = oBooks.Open("c:\\Book1.xlsx", oMissing, oMissing, 
oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, 
oMissing, oMissing, oMissing, oMissing, oMissing, oMissing); 

// Run the macros. 
RunMacro(oExcel, new Object[] { "Import" }); 
//RunMacro(oExcel, new Object[]{"DoKbTestWithParameter", 

} 
private void RunMacro(object oApp, object[] oRunArgs) 
{ 
oApp.GetType().InvokeMember("Run", 
System.Reflection.BindingFlags.Default | 
System.Reflection.BindingFlags.InvokeMethod, 
null, oApp, oRunArgs); 
} 

SELECT TSPRojectCodeID, EmployeeID, sum(HoursWorked) AS "Total Hours"
FROM tblTimesheetDetails
WHERE TimeSheetDate >= '2010/07/01' AND TimeSheetDate <= '2010/07/30' 
GROUP BY TSProjectCodeID, EmployeeID;

public string processSQL()
{
    string sql = null;
    string inSql = null;
    string firstPart = null;
    string lastPart = null;
    int selectStart = 0;
    int fromStart = 0;
    string[] fields = null;
    string[] sep = { "," };
    int i = 0;
    TextObject MyText;
    string startdate = fromDate.Value.ToString("yyyy/MM/dd");
    string todate = toDate.Value.ToString("yyyy/MM/dd");
    //inSql = @"Select EmployeeID,TSProjectCodeID,TaskCode,TimeSheetDate, from tblTimesheetDetails WHERE TimeSheetDate >= '" + startdate + "' AND TimeSheetDate <= '" + todate + "' AND TSProjectCodeID = '" + cmbprojects.Text.ToString() + "'";//ORDER BY TSProjectCode";
    inSql = @" Select DISTINCT TSProjectCodeID, EmployeeID, SUM(HoursWorked) AS 'Total_Hours', FROM tblTimesheetDetails WHERE TimeSheetDate >= '" + startdate + "' AND TimeSheetDate <= '" + todate + "' AND TSProjectCodeID = '" + cmbprojects.Text.ToString() + "'ORDER BY TSProjectCodeID, EmployeeID, HoursWorked";
    //inSql = textBox1.Text;
    inSql = inSql.ToUpper();

    selectStart = inSql.IndexOf("SELECT");
    fromStart = inSql.IndexOf("FROM");
    selectStart = selectStart + 15;
    firstPart = inSql.Substring(selectStart, (fromStart - selectStart));
    lastPart = inSql.Substring(fromStart, inSql.Length - fromStart);

    fields = firstPart.Split(',');
    firstPart = "";
    for (i = 0; i <= fields.Length - 1; i++)
    {
        if (i > 0)
        {
            firstPart = firstPart + ", " + fields[i].ToString() + " AS COLUMN" + (i + 1);
            firstPart.Trim();

            MyText = (TextObject)objRpt.ReportDefinition.ReportObjects[i];// + 1];
            MyText.Text = fields[i].ToString();
        }
        else
        {
            firstPart = firstPart + fields[i].ToString() + " AS COLUMN" + (i +1);// + 1);
            firstPart.Trim();

            MyText = (TextObject)objRpt.ReportDefinition.ReportObjects[i];// + 1];
            MyText.Text = fields[i].ToString();
        }
    }
    sql = "SELECT " + firstPart + " " + lastPart;
    return sql;
}