connection not closed error in c#?

Question

there a problem in my project when i try insert some info it gives me error like image in the link http://s21.postimg.org/gxkd7roh3/Capture.png error said that connection is not closed ?

Sanjeeb Lenka · Answer

try this modified code: 1st one: private void bindcombo_college_name() { OleDbCommand com = new OleDbCommand(); OleDbDataReader reader; com.Connection = db_con; if (db_con.State == ConnectionState.Closed) db_con.Open(); college_name.Items.Clear(); com.CommandText = "select * from colleges"; reader = com.ExecuteReader(); while(reader.Read()) { string combo_items = reader["college_name"].ToString(); college_name.Items.Add(combo_items);//college_name is a combobox } db_con.Close(); 2nd one: OleDbCommand com = new OleDbCommand(); OleDbDataReader reader; com.Connection = db_con; dept_name.Items.Clear(); if (db_con.State == ConnectionState.Closed) db_con.Open(); com.CommandText = "select * from [depts] inner join [colleges] on [colleges].college_code = [depts].college_code where [colleges].[college_name] = '" + college_name.Text + "'"; reader = com.ExecuteReader(); while (reader.Read()) { string combo_items = reader["dept_name"].ToString(); dept_name.Items.Add(combo_items);//college_name is a combobox } db_con.Close();

Prasenjit Dey · Answer

try this if (db_con.State == ConnectionState.Closed || db_con.State == ConnectionState.broken) db_con.Open(); if (db_con.State == ConnectionState.Open) db_con.Close();

honar abubakr · Answer

thank you friends for all answers

Iftikar Hussain · Answer

Hi, Try like this if (db_con.State != ConnectionState.Open) { db_con.Open(); } if (db_con.State == ConnectionState.Open) db_con.Close(); Regards, Iftikar

honar abubakr · Answer

i have insert form for inserting student info in the form i have 2 comboboxes one for college and the other for depts .... i bind the first combobox with a database column usin this methos private void bindcombo_college_name() { OleDbCommand com = new OleDbCommand(); OleDbDataReader reader; com.Connection = db_con; db_con.Open(); college_name.Items.Clear(); com.CommandText = "select * from colleges"; reader = com.ExecuteReader(); while(reader.Read()) { string combo_items = reader["college_name"].ToString(); college_name.Items.Add(combo_items);//college_name is a combobox } db_con.Close(); and i want in the second combobox to display only the depts of the college that i select in the first combobox i use the first combobox textchange event to do this with this code OleDbCommand com = new OleDbCommand(); OleDbDataReader reader; com.Connection = db_con; dept_name.Items.Clear(); db_con.Open(); com.CommandText = "select * from [depts] inner join [colleges] on [colleges].college_code = [depts].college_code where [colleges].[college_name] = '" + college_name.Text + "'"; reader = com.ExecuteReader(); while (reader.Read()) { string combo_items = reader["dept_name"].ToString(); dept_name.Items.Add(combo_items);//college_name is a combobox } db_con.Close(); it do the action that i want but when i click the insert button it inserts data and gives connection not closed error

Sandeep Singh Shekhawat · Answer

use these usings using System.Data.SqlClient; using System.Data; write your connection in this if block if (db_con.State == ConnectionState .Closed) { db_con.Open(); }

Sunny Sharma · Answer

Honor, we cannot help you with that little information, share your code and provide details.

connection not closed error in c#?

Answers (7)