Question

I am getting an error when attempting to call a stored proc from my asp.net page.

e.Message = “Conversion failed when
converting character string to
smalldatetime data type.”

The stored proc is being called by:

The asp.net code that is calling the stored proc is:

//Display search results in GridView; 
SqlConnection con = new SqlConnection(strConn); 
//string sqlItemSearch = "usp_Item_Search"; 
SqlCommand cmdItemSearch = new SqlCommand(sqlItemSearch, con); 
cmdItemSearch.CommandType = CommandType.StoredProcedure; 

cmdItemSearch.Parameters.Add(new SqlParameter("@Item_Num", SqlDbType.VarChar, 30)); 
cmdItemSearch.Parameters["@Item_Num"].Value = txtItemNumber.Text.Trim(); 

cmdItemSearch.Parameters.Add(new SqlParameter("@Search_Type", SqlDbType.Int)); 
cmdItemSearch.Parameters["@Search_Type"].Value = ddlSearchType.SelectedItem.Value; 

cmdItemSearch.Parameters.Add(new SqlParameter("@Vendor_Num", SqlDbType.VarChar, 10)); 
cmdItemSearch.Parameters["@Vendor_Num"].Value = txtVendorNumber.Text.Trim(); 

cmdItemSearch.Parameters.Add(new SqlParameter("@Search_User_ID", SqlDbType.Int)); 
cmdItemSearch.Parameters["@Search_User_ID"].Value = ddlSeachUser.SelectedItem.Value; 

if (!string.IsNullOrEmpty(txtStartDate.Text)) 
{ 
    cmdItemSearch.Parameters.Add(new SqlParameter("@StartDate", SqlDbType.DateTime)); 
    cmdItemSearch.Parameters["@StartDate"].Value = Convert.ToDateTime(txtStartDate.Text.Trim()); 
} 
else 
{ 
    cmdItemSearch.Parameters.Add(new SqlParameter("@StartDate", SqlDbType.DateTime)); 
    cmdItemSearch.Parameters["@StartDate"].Value = Convert.ToDateTime("01/01/1996"); 
} 

if (!string.IsNullOrEmpty(txtEndDate.Text)) 
{ 
    cmdItemSearch.Parameters.Add(new SqlParameter("@EndDate", SqlDbType.DateTime)); 
    cmdItemSearch.Parameters["@EndDate"].Value = Convert.ToDateTime(txtEndDate.Text.Trim()); 
} 
else 
{ 
    cmdItemSearch.Parameters.Add(new SqlParameter("@EndDate", SqlDbType.DateTime)); 
    cmdItemSearch.Parameters["@EndDate"].Value = Convert.ToDateTime(DateTime.Now); 
} 
con.Open(); 

SqlDataAdapter ada = new SqlDataAdapter(cmdItemSearch); 
DataSet ds = new DataSet(); 
ada.Fill(ds); 

    gvSearchDetailResults.DataSource = ds; 
    gvSearchDetailResults.DataBind(); 
    pnlSearchResults.Visible = true; 

Any ideas what would be causing the error?

Answer 1

The problem is caused by one of these lines:

cmdItemSearch.Parameters["@EndDate"].Value = Convert.ToDateTime(txtEndDate.Text.Trim());

or

cmdItemSearch.Parameters["@StartDate"].Value = Convert.ToDateTime(txtStartDate.Text.Trim());

or

cmdItemSearch.Parameters["@StartDate"].Value = Convert.ToDateTime("01/01/1996");

It may be caused by incorrectly entered values or locale problems. If you do not need to output validation messages, then you can use DateTime.TryParse() static function to parse the entered date and time.

I would do it this way:

DateTime date;
cmdItemSearch.Parameters.Add(new SqlParameter("@StartDate", SqlDbType.DateTime)); // note this line was unnecessary duplicated 
if (!string.IsNullOrEmpty(txtStartDate.Text) && DateTime.TryParse(txtStartDate.Text.Trim(), out date)) 
    cmdItemSearch.Parameters["@StartDate"].Value = date; 
else 
    cmdItemSearch.Parameters["@StartDate"].Value = DateTime.MinValue;