Error in OleDBConnection : Object reference not set to an instance of an object

[sksandz]

I am running the following code. It executes when the value of variable i is 1 and when the loop continues and value of i becomes 2 i am getting error "Object reference not set to an instance of an object" in the cmdSearch.CommandText line in the code. . There is no problem with connection string. It successfully retrieves when i = 1. Can anybody help me out what is the problem. Please post with corrected code if anybody can help. =========================================== for (int i=1; i <= objFolder.Items.Count; i++) { System.Data.OleDb.OleDbConnection odbSearch = new System.Data.OleDb.OleDbConnection(); System.Data.OleDb.OleDbCommand cmdSearch = new System.Data.OleDb.OleDbCommand(); odbSearch.ConnectionString = strConn; cmdSearch.Connection = odbSearch; item = (Outlook.ContactItem) objFolder.Items.Item(i); string em = item.Email1Address; cmdSearch.CommandText = "select * from Outlook_Contacts where FirstName='"+fn.ToString().Trim()+"' and LastName='"+ln.ToString().Trim()+"'"; odbSearch.Open(); OleDbDataReader rdrSearch = cmdSearch.ExecuteReader(); while( rdrSearch.Read()) { RecordFlag = true; } odbSearch.Close(); } ===========================================

[big_trev]

What are fn and ln? Where are they defined?

[sksandz]

fn and ln are declared outside and the values are properly getting passed to those variables. The code executes when i=1 and when the value of i becomes 2 the error occurs. There is no problem with connection string also. only when the code executes to the commandtext line it shows the error. that too i am getting one record successfully(when i = 1). hope this helps

[big_trev]

well, some thing is null. It is either item, cmdSearch, fn or ln. can you step through it in VS and check?

[mav northwind]

Like bigtrev said, just step through and check fn and ln. Or perhaps you got the line number wrong and item is null. Anyway, just step through and check. Btw. you know that building SQL commands the way you do is highly vulnerable to SQL injection? You should use parameterized queries instead. Regards, mav

[Anonymous]

I have done that. I am getting one record ie. when the value of i = 1. When the value of i increases to 2 then in the commandtext line this error occurs. And also fn and ln are fine. Can you please tell me how to solve it?