SP - CodError with CAML query,

Question

I want go get last record field value from my SPList with CAML query. Really code working but gives me following ERROR...

My Code:

void ddCarNumber_TextChanged(object sender, EventArgs e)
{
    try
    {

       SPWeb myWEB = SPContext.Current.Web;

        SPList myList = myWEB.Lists["WayBill"];

        SPQuery myQuery = new SPQuery();
        myQuery.Query = @"<OrderBy>
                            <FieldRef Name='Created' Ascending='FALSE' /> 
                        </OrderBy> 
                        <Where>
                            <Eq>
                                <FieldRef Name='CarNumber1'/>
                                <Value Type='Text'>" + ddCarNumber.Text + @"</Value>
                            </Eq>
                        </Where>";

           SPListItemCollection myItemCol = myList.GetItems(myQuery);

            if (myItemCol.Count > 0)
            {
                string myEndMil = myItemCol[0]["endMil"].ToString();

                string digitsOnly = String.Empty;
                foreach (char c in myEndMil)
                {
                    if (c >= '0' && c <= '9')
                    {
                        digitsOnly += c;
                    }
                }

                txtStartMil.Text = digitsOnly;
            }
            else
            {
                txtStartMil.Text = string.Empty;
            }
    }
    catch (Exception ex)
    {   
       lblError.Text = ex.ToString();
    }
}

Error is :

System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values. at Microsoft.SharePoint.SPListItemCollection.get_Item(Int32 iIndex) at Lirex.WayBillModule.ddCarNumber_TextChanged(Object sender, EventArgs e)

Answer 1

Try this below method:

void ddCarNumber_TextChanged(object sender, EventArgs e)
{
    try
    {

       SPWeb myWEB = SPContext.Current.Web;

        SPList myList = myWEB.Lists["WayBill"];

        SPQuery myQuery = new SPQuery();
        myQuery.Query = "<OrderBy><FieldRef Name='Created' Ascending='FALSE' /></OrderBy><Where><Eq><FieldRef Name='CarNumber1'/><Value Type='Text'>" + ddCarNumber.Text + "</Value></Eq></Where>";

           SPListItemCollection myItemCol = myList.GetItems(myQuery);

            if (myItemCol.Count > 0)
            {
                if(myItemCol[0]["endMil"] != null)
                {
                    string myEndMil = myItemCol[0]["endMil"].ToString();

                    string digitsOnly = String.Empty;
                    foreach (char c in myEndMil)
                    {
                        if (Char.IsDigit(c))
                        {
                            digitsOnly += c;
                        }
                    }
                }
                txtStartMil.Text = digitsOnly;
            }
            else
            {
                txtStartMil.Text = string.Empty;
            }
    }
    catch (Exception ex)
    {   
       lblError.Text = ex.ToString();
    }
}

Hope this will help you!

Answer 2

Here string myEndMil = myItemCol[0]["endMil"].ToString(); you are assuming you have gotten at least one result back. That might not be the case!

You should check first that myItemCol.Count > 0

There is another possible issue at the same line (string myEndMil = myItemCol[0]["endMil"].ToString();)

You are requesting a column endMil that you might not have.

Answer 3

Can you try putting <RowLimit>1</RowLimit> in the Query. The row limit will return only the one last item.

Answer 4

Try this code. Added some safe checks

void ddCarNumber_TextChanged(object sender, EventArgs e)
{
    try
    {    
        SPWeb myWEB = SPContext.Current.Web;

        SPList myList = myWEB.Lists.TryGetList("WayBill");
        if(myList != null)
        {
           SPQuery myQuery = new SPQuery();
           myQuery.Query = @"<OrderBy>
                            <FieldRef Name='ID' Ascending='FALSE' /> 
                        </OrderBy> 
                        <Where>
                            <Eq>
                                <FieldRef Name='CarNumber1'/>
                                <Value Type='Text'>" + ddCarNumber.Text + @"</Value>
                            </Eq>
                        </Where>";

            myQuery.RowLimit = 1; 
            SPListItemCollection myItemCol = myList.GetItems(myQuery);

            if (myItemCol != null && myItemCol.Count > 0)
            {
                string digitsOnly = String.Empty;
                string myEndMil = String.Empty;
                if(myItemCol[0]["endMil"] != null)
                {
                   myEndMil = Convert.ToString(myItemCol[0]["endMil"]);    

                   foreach (char c in myEndMil)
                   {
                       if (c >= '0' && c <= '9')
                       {
                           digitsOnly += c;
                       }
                   }
                }
                txtStartMil.Text = digitsOnly;
            }
            else
            {
                txtStartMil.Text = String.Empty;
            }
        }
    }
    catch (Exception ex)
    {   
       lblError.Text = ex.ToString();
    }
}

• While fetching a list use TryGetList like this myWEB.Lists.TryGetList("WayBill");
• Use ID Column possibly when performing a ORDER BY operation. Since ID is indexed column, query execute faster.
• You must always do a null check when query is fired and data is assigned to SPListItemCollection
• You should try to keep practice of using Convert.ToString() instead of .ToString() for ex Convert.ToString(myItemCol[0]["endMil"]); and not myItemCol[0]["endMil"].ToString()
• Also check if column exists or not. if(myItemCol[0]["endMil"] != null)