string ConnectionString = WebConfigurationManager.ConnectionStrings["dbnameConnectionString"].ConnectionString;
SqlConnection myConnection = new SqlConnection(ConnectionString);
myConnection.Open();
try
{
string qry = "UPDATE customers SET firstname=#firstname WHERE cid=1";
SqlCommand insertQuery = new SqlCommand(qry, myConnection);
insertQuery.Parameters.Add(new SqlParameter("#firstname", txtFirstname.Text));
insertQuery.ExecuteNonQuery();
myConnection.Close();
}
catch (Exception ee)
{
}
Any suggestions?
A little cleanup of your code you may like to try (you should dispose IDisposable objects):
string ConnectionString = // ...
using (var connection = new SqlConnection(ConnectionString))
using (var command = connection.CreateCommand())
{
connection.Open();
command.CommandText = "UPDATE customers SET firstname = #firstname WHERE cid=1";
command.Parameters.AddWithValue("#firstname", txtFirstname.Text);
var rowsUpdated = command.ExecuteNonQuery();
}
Related
I was trying to connectMs_sql database in asp.net but server error of network path not found... it is not able to establish connection to sql server...comes while in gridview it is taking it as sqldatasource perfectly
This for customized class to call the ADO.Net. Please use this and let me know if you have any doubts.
public class DbConnectionHelper {
public DataSet DBConnection(string TableName, SqlParameter[] p, string Query, CommandType cmdText) {
string connString = # "your connection string here";
//Object Declaration
DataSet ds = new DataSet();
SqlConnection con = new SqlConnection();
SqlCommand cmd = new SqlCommand();
SqlDataAdapter sda = new SqlDataAdapter();
try {
//Get Connection string and Make Connection
con.ConnectionString = connString; //Get the Connection String
if (con.State == ConnectionState.Closed) {
con.Open(); //Connection Open
}
if (cmdText == CommandType.StoredProcedure) //Type : Stored Procedure
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = Query;
if (p.Length > 0) // If Any parameter is there means, we need to add.
{
for (int i = 0; i < p.Length; i++) {
cmd.Parameters.Add(p[i]);
}
}
}
if (cmdText == CommandType.Text) // Type : Text
{
cmd.CommandType = CommandType.Text;
cmd.CommandText = Query;
}
if (cmdText == CommandType.TableDirect) //Type: Table Direct
{
cmd.CommandType = CommandType.Text;
cmd.CommandText = Query;
}
cmd.Connection = con; //Get Connection in Command
sda.SelectCommand = cmd; // Select Command From Command to SqlDataAdaptor
sda.Fill(ds, TableName); // Execute Query and Get Result into DataSet
con.Close(); //Connection Close
} catch (Exception ex) {
throw ex; //Here you need to handle Exception
}
return ds;
}
}
I am trying to get details of an account in a row using the Username instead of id. I have limited knowledge on this matter so im only stuck with the code that i learned in class.
I have tried changing variables, but probably wont help and the code i have provided below, would not retrieve any data from the database...
(Username are retrieved from previous page and yes it did show up in this page)
This is the code used on previous page: (code is placed on a button)
string username = Session["Username"].ToString();
Response.Redirect("EditAccountDetail.aspx?Username="+ username);
private DataTable GetData()
{
string constr = ConfigurationManager.ConnectionStrings["myDbConnectionString"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand("SELECT * FROM Guest"))
{
using (SqlDataAdapter sda = new SqlDataAdapter())
{
cmd.Connection = con;
sda.SelectCommand = cmd;
using (DataTable dt = new DataTable())
{
sda.Fill(dt);
return dt;
}
}
}
}
}
This is the code im working on right now:
String Uname = Request.QueryString["Username"];
string constr = ConfigurationManager.ConnectionStrings["MyDbConnectionString"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand("SELECT * FROM Guest WHERE Username='" + Uname+"'"))
{
using (SqlDataAdapter sda = new SqlDataAdapter())
{
cmd.Connection = con;
sda.SelectCommand = cmd;
using (DataTable dt = new DataTable())
{
sda.Fill(dt);
foreach (DataRow row in dt.Rows)
{
string id = row["Id"].ToString();
string Full_name = row["Full_name"].ToString();
string Username = row["Username"].ToString();
string Password = row["Password"].ToString();
string Email = row["Email"].ToString();
string DOB = row["DOB"].ToString();
string Gender = row["Gender"].ToString();
this.HiddenField1.Value = id;
this.TextBox_Name.Text = Full_name;
this.TextBox_Username.Text = Username;
this.TextBox_Password.Text = Password;
this.TextBox_Email.Text = Email;
this.TextBox_DOB.Text = DOB;
this.RadioButtonList_Gender.Text = Gender;
}
}
}
}
}
This is the code in the button:
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["myDbConnectionString"].ConnectionString);
try
{
string query = "UPDATE Guest SET Full_name=#Full_name, Username=#Username, Password=#Password, Email=#Email, DOB=#DOB, Gender=#Gender WHERE Id=#id";
SqlCommand cmd = new SqlCommand(query, con);
cmd.Parameters.AddWithValue("#id", HiddenField1.Value);
cmd.Parameters.AddWithValue("#Full_name", TextBox_Name.Text);
cmd.Parameters.AddWithValue("#Username", TextBox_Username.Text);
cmd.Parameters.AddWithValue("#Password", TextBox_Password.Text);
cmd.Parameters.AddWithValue("#Email", TextBox_Email.Text);
cmd.Parameters.AddWithValue("#DOB", TextBox_DOB.Text);
cmd.Parameters.AddWithValue("#Gender", RadioButtonList_Gender.Text);
con.Open();
cmd.ExecuteNonQuery();
Response.Redirect("GuestMenu.aspx");
con.Close();
}
catch (Exception ex)
{
Response.Write("Error: " + ex.ToString());
}
If you are redirecting to the "GuestMenu" page, then you have to add username in the query string so that you can retrieve this on the page.
Response.Redirect("GuestMenu.aspx?Username="+TextBox_Username.Text);
By seeing your current code, you should be getting some error. Please post the error details if any.
You can try changing the query as below and check for database result
new SqlCommand("SELECT * FROM Guest WHERE Username='" + Uname + "'")
I'm new to ASP.Net & SQL Server and have the following code:
protected void btnShowData_Click(object sender, EventArgs e)
{
string connectionString;
SqlConnection cnn;
connectionString = #"Data Source=DESKTOP-RV7DDL4;Initial Catalog=Demodb
;User ID=DESKTOP-RV7DDL4\dbname;Password=test123";
cnn = new SqlConnection(connectionString);
SqlCommand command;
SqlDataReader dataReader;
String sql, Output = "";
sql = "Select TutorialID, TutorialName from demotb";
command = new SqlCommand(sql, cnn);
dataReader = command.ExecuteReader();
while (dataReader.Read())
{
Output = Output + dataReader.GetValue(0) + " - " + dataReader.GetValue(1) + "</br>";
}
Response.Write(Output);
dataReader.Close();
command.Dispose();
cnn.Close();
lblName.Visible = false;
txtName.Visible = false;
lstLocation.Visible = false;
chkC.Visible = false;
chkASP.Visible = false;
rdMale.Visible = false;
rdFemale.Visible = false;
btnSubmit.Visible = false;
}
When I run the project I receive the following error:
An exception of type 'System.InvalidOperationException' occurred in System.Data.dll but was not handled in user code
Additional information: ExecuteReader requires an open and available Connection. The connection's current state is closed.
I thought the connection was made so not sure why it says the db is closed?
Try to to explicitly open the connection via the Open method on the SQL connection class.
Perhaps a using statement is more appropriate here. Like so:
using (var cnn = new SqlConnection(connectionString))
{
// Use the connection
}
Thanks for your help. I re-jigged things around and added the .Open method and it works!
string connectionString = null;
SqlConnection cnn;
SqlCommand command;
string sql, Output = "";
connectionString = #"Data Source=DESKTOP-RV7DDL4\SQLEXPRESS;Initial Catalog=DemoDBase
;User ID=sa;Password=test1234";
cnn = new SqlConnection(connectionString);
sql = "Select TutorialID, TutorialName from demoTable";
cnn.Open();
command = new SqlCommand(sql, cnn);
SqlDataReader dataReader;
dataReader = command.ExecuteReader();
while (dataReader.Read())
{
Output = Output + dataReader.GetValue(0) + " - " + dataReader.GetValue(1) + "</br>";
}
Response.Write(Output);
dataReader.Close();
command.Dispose();
cnn.Close();
i am using a datalist to display videos but i am trying to get it working now with the where clasue ...where the name is equal to wrd.mp4 i am getting the following error,
$exception {"The multi-part identifier \"wrd.mp4\" could not be bound."} System.Exception {System.Data.SqlClient.SqlException}
private void BindGrid()
{
string strConnString = ConfigurationManager.ConnectionStrings["DatabaseConnectionString1"].ConnectionString;
using (SqlConnection con = new SqlConnection(strConnString))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = "select Id, Name from tblFiles where Name=wrd.mp4";
cmd.Connection = con;
con.Open();
DataList1.DataSource = cmd.ExecuteReader();
DataList1.DataBind();
con.Close();
}
}
}
}
You need to use quotes:
cmd.CommandText = "select Id, Name from tblFiles where Name='wrd.mp4'";
Below code is written to call parameterized select query in asp.net
public bool checkConflictTime()
{
bool TimeExists = false;
DataSet ds = new DataSet();
SqlConnection sqlconn = new SqlConnection();
sqlconn.ConnectionString = ConfigurationManager.ConnectionStrings["TestConn"].ConnectionString;
string sql = #"SELECT * FROM Images WHERE starttime= #starttime AND endtime = #endtime";
SqlCommand sqlcommand = new SqlCommand(sql,sqlconn);
//sqlcommand.Connection = sqlconn;
//string sql = "CheckConflictTimings";
sqlcommand.CommandType = CommandType.Text;
sqlcommand.CommandText = sql;
sqlcommand.Parameters.Add(new SqlParameter("#starttime", ddlStartTime.SelectedItem.Text));
sqlcommand.Parameters.Add(new SqlParameter("#endtime", ddlEndTime.SelectedItem.Text));
SqlDataAdapter da = new SqlDataAdapter(sql, sqlconn);
try
{
da.Fill(ds);
if (ds.Tables[0].Rows.Count > 0)
{
TimeExists = true;
}
}
catch (Exception ex)
{
}
finally
{
sqlconn.Close();
sqlconn.Dispose();
}
return TimeExists;
}
Is there something wrong? it threw error of :Must declare the scalar variable "#starttime"
when filling data adapter.
Try
SqlDataAdapter da = new SqlDataAdapter(sqlcommand);
Try
sqlcommand.Parameters.Add(new SqlParameter("starttime", ddlStartTime.SelectedItem.Text));
I don't think you need the # prefix when adding the parameter.
I think you're not passing your command as a SelectCommand to the adapter.
da.SelectCommand = sqlcommand;
Try
sqlcommand.Parameters.AddWithValue("#starttime",ddlStartTime.SelectedItem.Text);
instead of
sqlcommand.Parameters.Add(new SqlParameter("#starttime", ddlStartTime.SelectedItem.Text));