Gridview Update error - c#

I am doing a small application in ASP.net(C#) with MS Access. I have a Gridview where I have a "Update" command. During run time I had put break point in RowUpdating() method. Everything works on well with no errors, the parameters are getting updated in the code behind. But in the output, gridview is not updating and also not in DB.
HERE IS THE CODE:
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
string ID = GridView1.Rows[e.RowIndex].Cells[1].Text;
string CName= ((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text;
string AName = ((TextBox)GridView1.Rows[e.RowIndex].Cells[3].Controls[0]).Text;
string APhone = ((TextBox)GridView1.Rows[e.RowIndex].Cells[4].Controls[0]).Text;
string AEmail = ((TextBox)GridView1.Rows[e.RowIndex].Cells[5].Controls[0]).Text;
string Note = ((TextBox)GridView1.Rows[e.RowIndex].Cells[6].Controls[0]).Text;
UpdateRecord(ID, CName, AName, APhone, AEmail, Note); // GridView1.EditIndex = -1; BindGridView();
}
UpdateRecord() Method:
The update method works well, during the run with breakpoints all the parameters get the updated values but it is not shown in the gridview and not updated in DB
private void UpdateOrAddNewRecord(string ID, string CName, string AName, string APhone, string AEmail, string Note)
{
OleDbConnection connection = null;
string conStr = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Documents and Settings\arjun.giridhar\Desktop\db1.mdb;Persist Security Info=False";
string sqlStatement = "UPDATE Carriers" + " SET CarrierName = #CarrierName, AccountRepName = #AccountRepName, AccountRepContactPhone = #AccountRepContactPhone, AccountRepEmail= #AccountRepEmail, Notes=#Notes" + " WHERE CarrierID = #CarrierID";
try
{
connection = new OleDbConnection(conStr);
connection.Open();
OleDbCommand cmd = new OleDbCommand(sqlStatement, connection);
cmd.Parameters.AddWithValue("#CarrierID", ID);
cmd.Parameters.AddWithValue("#CarrierName", CName);
cmd.Parameters.AddWithValue("#AccountRepName", AName);
cmd.Parameters.AddWithValue("#AccountRepContactPhone", APhone);
cmd.Parameters.AddWithValue("#AccountRepEmail", AEmail);
cmd.Parameters.AddWithValue("#Notes", Note);
cmd.CommandType = CommandType.Text;
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
string msg = "Update Error:";
msg += ex.Message;
throw new Exception(msg);
}
finally
{
connection.Close();
}
}
BindGridView() Method:
private void BindGridView()
{
DataTable dt = new DataTable();
OleDbConnection connection = new OleDbConnection(conStr);
try
{
connection.Open();
string sqlStatement = "SELECT * FROM Carriers";
OleDbCommand cmd = new OleDbCommand(sqlStatement, connection);
OleDbDataAdapter sqlDa = new OleDbDataAdapter(cmd);
sqlDa.Fill(dt);
if (dt.Rows.Count > 0)
{
GridView1.DataSource = dt;
GridView1.DataSourceID = string.Empty;
GridView1.DataBind();
}
}
catch (System.Data.SqlClient.SqlException ex)
{
string msg = "Fetch Error:";
msg += ex.Message;
throw new Exception(msg);
}
finally
{
connection.Close();
}
}
Kindly give me a solution.
Regards,
Arjun

I found another article here: Gridview not updating value which said that this is caused by binding your grid in the Page_Load and not checking for postback. I changed my Page_load to:
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
BindGridView();
}
}
That worked.

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SQL DataReader: Invalid attempt to read when no data is present to label

I am trying to use a SqlDataReader to run queries on two tables where the 1st column in the Selection table is a foreign key referencing to the Items table, and then display the results in labels, but I keep getting the error:
Invalid attempt to read when no data is present.
Here is my code:
public partial class Read : System.Web.UI.Page
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if (!IsPostBack)
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GetInfo();
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}
private void GetInfo() {
try
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cmd = new SqlCommand(sqlsel, conn);
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I'm pretty new at this so please bear with me.

C# How to Update/Change the specific letter/number of a string in database

I ask these question coz i really don't know how i'm gonna do that and is it possible to do that?
What i want is to update/change here for example STA-100418-100 in database values, update/change the 100 based on the user input, like 50 it will be STA-100418-50.
Here's the provided image to be more precise
As you can see on the image, there's a red line, if user update the quantity as 60, In Codeitem STA-100418-100 should be STA-100418-60
I really have no idea on how to do that. I hope someone would be able to help me
here's my code for updating the quantity
private void btn_ok_Click(object sender, EventArgs e)
{
using (var con = SQLConnection.GetConnection())
{
using (var selects = new SqlCommand("Update Product_Details set quantity = quantity - #Quantity where ProductID= #ProductID", con))
{
selects.Parameters.Add("#ProductID", SqlDbType.VarChar).Value = _view.txt_productid.Text;
selects.Parameters.Add("#Quantity", SqlDbType.Int).Value = Quantity;
selects.ExecuteNonQuery();
}
}
}
Here's the code to get that format in codeitems
string date = DateTime.Now.ToString("MMMM-dd-yyyy");
string shortdate = DateTime.Now.ToString("-MMddy-");
private void Quantity_TextChanged(object sender, EventArgs e)
{
Code.Text = Supplier.Text.Substring(0, 3) + shortdate + Quantity.Text;
}
Here's what I use to update SQL-Server
public static DataTable GetSqlTable(string sqlSelect)
{
string conStr = ConfigurationManager.ConnectionStrings["connString"].ConnectionString;
DataTable table = new DataTable();
SqlConnection connection = new SqlConnection(conStr);
try
{
connection.Open();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
if (connection.State != ConnectionState.Open)
{
return table;
}
SqlCommand cmd = new SqlCommand(sqlSelect, connection);
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
try
{
adapter.Fill(table);
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
throw;
}
connection.Close();
connection.Dispose();
return table;
}
public static void GetSqlNonQuery(string sqlSelect)
{
string newObject = string.Empty;
string strConn = ConfigurationManager.ConnectionStrings["connString"].ConnectionString;
SqlConnection connection = new SqlConnection(strConn);
connection.Open();
if (connection.State != ConnectionState.Open)
{
return;
}
try
{
SqlCommand cmd = new SqlCommand(sqlSelect, connection);
cmd.ExecuteNonQuery();
connection.Close();
connection.Dispose();
}
catch (Exception ex)
{
string x = ex.Message + ex.StackTrace;
throw;
}
}
Here's how to use it
DataTable dt = GetSqlTable("select Quantity from product where CodeItem = 'STA-100418-100'");
string strQuantity = dt.Rows[0]["Quantity"].ToString();
GetSqlNonQuery(string.Format("UPDATE product SET CodeItem = '{0}' WHERE = 'STA-100418-100'", strQuantity));
User will input everytime in the Quantity textbox, the textchanged event of Quantity will be hit and you will get new value everytime with the same date but with different quantity. So you can use the Code.Text to update the CodeDateTime value or you can use a global variable instead of Code.Text and use it to update the column.
string date = DateTime.Now.ToString("MMMM-dd-yyyy");
string shortdate = DateTime.Now.ToString("-MMddy-");
private void Quantity_TextChanged(object sender, EventArgs e)
{
Code.Text = Supplier.Text.Substring(0, 3) + shortdate + Quantity.Text;
}
using (var con = SQLConnection.GetConnection())
{
using (var selects = new SqlCommand("Update Product_Details set quantity = quantity - #Quantity, CodeItem = #Code where ProductID= #ProductID", con))
{
selects.Parameters.Add("#ProductID", SqlDbType.VarChar).Value = _view.txt_productid.Text;
selects.Parameters.Add("#Quantity", SqlDbType.Int).Value = Quantity;
selects.Parameters.Add("#Code", Code.Text);
}
}
as I understand it you need MSSQL String Functions
SELECT rtrim(left(Codeitem,charindex('-', Codeitem))) + ltrim(str(Quantity)) FROM ...
For detailed information
Using MySql, Substring the code item and then concatenate the quantity.
UPDATE Product_Details SET quantity = #quantity,CodeIem = CONCAT(SUBSTR(#code,1,11),#quantity) WHERE ProductID= #ProductID

C# update statement not updating when update button clicked

i am creating c# project so far insert and delete buttons are working but when i hit update button it gives data has not been updated and i cant see what is wrong with my code please help
public bool Update(Classre c)
{
bool isSuccess = false;
SqlConnection conn = new SqlConnection(myconnstring);
try
{
string sql = "UPDATE Class SET ClassName=#ClassName,ClassLevel=#ClassLevel WHERE ClassID=#ClassID";
SqlCommand cmd = new SqlCommand(sql, conn);
cmd.Parameters.AddWithValue("#ClassName", c.ClassName);
cmd.Parameters.AddWithValue("#ClassLevel", c.ClassLevel);
conn.Open();
int rows = cmd.ExecuteNonQuery();
if (rows > 0)
{
isSuccess = true;
}
else
{
isSuccess = false;
}
}
catch (Exception ex)
{
}
finally
{
conn.Close();
}
return isSuccess;
}
and this is my update button code where i call the class that holds my update code
private void button3_Click(object sender, EventArgs e)
{
c.ClassID = int.Parse(textBox1.Text);
c.ClassName = textBox2.Text;
c.ClassLevel = comboBox1.Text;
bool success = c.Update(c);
if (success == true)
{
// label4.Text = "Data Has been updated";
MessageBox.Show("Data Has been updated");
DataTable dt = c.Select();
dataGridView1.DataSource = dt;
}
else
{
//label4.Text = "Data Has not been updated";
MessageBox.Show("Data Has not been updated");
}
}
I would prefer to use a stored procedure instead of pass through sql but you could greatly simplify this. As stated above your try/catch is worse than not having one because it squelches the error.
public bool Update(Classre c)
{
USING(SqlConnection conn = new SqlConnection(myconnstring))
{
string sql = "UPDATE Class SET ClassName = #ClassName, ClassLevel = #ClassLevel WHERE ClassID = #ClassID";
USING(SqlCommand cmd = new SqlCommand(sql, conn))
{
cmd.Parameters.Add("#ClassName", SqlDbType.VarChar, 4000).Value = c.ClassName;
cmd.Parameters.Add("#ClassLevel", SqlDbType.Int).Value = c.ClassLevel;
cmd.Parameters.Add("#ClassID", SqlDbType.Int).Value = c.ClassID;
conn.Open();
int rows = cmd.ExecuteNonQuery();
return rows > 0;
}
}
}

Error with loading and updating form data

I have a form in ASP.NET that loads data if it exists for the user, and then allows them to update. So in Page_Load I have:
protected void Page_Load(object sender, EventArgs e)
{
if (!CheckAndAddRecord(_currentUser.UserID))
{
CreateEntryPoint(_currentUser.UserID);
}
else
{
DataView dv = LoadApplicationData(_currentUser.UserID);
foreach (DataRowView rowView in dv)
{
DataRow row = rowView.Row;
_applicationId = row["id"].ToString();
txtProjectNumber.Text = row["ProjectNumber"].ToString();
if (String.IsNullOrEmpty(chkSignedNDANo.ToString()) || String.IsNullOrEmpty(chkSignedNDAYes.ToString()))
{
chkSignedNDANo.Checked = Convert.ToBoolean(row["SignedNDAOnFile"]);
chkSignedNDAYes.Checked = Convert.ToBoolean(row["SignedNDAOnFile"]);
}
txtDateWritten.Text = row["DateWritten"].ToString();
}
}
}
It calls this method:
public bool CheckAndAddRecord(int UserId)
{
string connStr = ConfigurationManager.ConnectionStrings["SiteSqlServer"].ConnectionString;
SqlConnection conn = new SqlConnection(connStr);
SqlCommand cmd = new SqlCommand("CheckUserInTemp", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add(new SqlParameter("#SubmittedBy", UserId));
SqlDataAdapter dap = new System.Data.SqlClient.SqlDataAdapter(cmd);
DataSet ds = new DataSet();
// open conn
if (conn.State == ConnectionState.Closed)
conn.Open();
// fill
dap.Fill(ds);
// close the conn
if (conn.State == ConnectionState.Open)
conn.Close();
bool boolRecordExist = false;
if (ds.Tables[0].DefaultView.Count == 0)
{
boolRecordExist = false;
}
else
{
boolRecordExist = true;
}
return boolRecordExist;
}
This seems to work and populate the fields correctly. But then to update I call a Button click, which calls this method:
public void UpdateRecordInTemp(int appId, string projectNumber)
{
string connStr = ConfigurationManager.ConnectionStrings["SiteSqlServer"].ConnectionString;
SqlConnection conn = new SqlConnection(connStr);
SqlCommand cmd = new SqlCommand("CPC_ProposalUpdateTemp", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#id", appId);
cmd.Parameters.AddWithValue("#ProjectNumber", txtProjectNumber.Text);
try
{
conn.Open();
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw new Exception("Exception adding coupon. " + ex.Message);
}
finally
{
conn.Close();
}
}
The problem is the fields passed always contain the old values. So if the value when entering the page is "123" and I change it to "abc" and click the button, "123" is passed instead of "abc".
Sorry for the long post, I wanted to get all the details in. I am baffled by this. Thanks!
At page Load check IsPostBack property in if. It seems that your code is executing on every page load.
if(!IsPostBack)
{
// Do your work
}
UPDATE
In your code method UpdateRecordInTemp(int appId, string projectNumber) you are not using projectNumber instead you are using txtProjectNumber.Text

SqlDataAdapter.Update or SqlCommandBuilder not working

I have a form with a datagrid, which is populated wih data from a sqlserver database. The datagrid populates fine but I am having trouble posting back the changes made by the user, to the table in the sql database. My forms code is as follows:
public partial class frmTimesheet : Form
{
private DataTable tableTS = new DataTable();
private SqlDataAdapter adapter = new SqlDataAdapter();
private int currentTSID = 0;
public frmTimesheet()
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InitializeComponent();
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private void frmTimesheet_Load(object sender, EventArgs e)
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string strUser = cUser.currentUser;
cMyDate cD = new cMyDate(DateTime.Now.ToString());
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txtDate.Text = date.ToString();
cboTSUser.DataSource = cUser.GetListOfUsers("active");
cboTSUser.DisplayMember = "UserID";
cboTSUser.Text = strUser;
CheckForTimeSheet();
PopulateTimeSheet();
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private void CheckForTimeSheet()
{
string strUser = cboTSUser.Text;
cMyDate cD = new cMyDate(txtDate.Text);
DateTime date = cD.GetDate();
int newTSID = cTimesheet.TimeSheetExists(strUser, date);
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{
tableTS.Clear();
if (newTSID == 0)
{
MessageBox.Show("Create TimeSheet");
}
else
{
this.currentTSID = newTSID;
}
}
}
private void PopulateTimeSheet()
{
try
{
string sqlText = "SELECT EntryID, CaseNo, ChargeCode, StartTime, FinishTime, Units " +
"FROM tblTimesheetEntries " +
"WHERE TSID = " + this.currentTSID + ";";
SqlConnection linkToDB = new SqlConnection(cConnectionString.BuildConnectionString());
SqlCommand sqlCom = new SqlCommand(sqlText, linkToDB);
SqlDataAdapter adapter = new SqlDataAdapter(sqlCom);
adapter.SelectCommand = sqlCom;
SqlCommandBuilder builder = new SqlCommandBuilder(adapter);
adapter.Fill(tableTS);
dataTimesheet.DataSource = tableTS;
}
catch (Exception eX)
{
string eM = "Error Populating Timesheet";
cError err = new cError(eX, eM);
MessageBox.Show(eM + Environment.NewLine + eX.Message);
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}
private void txtDate_Leave(object sender, EventArgs e)
{
CheckForTimeSheet();
PopulateTimeSheet();
}
private void cboTSUser_DropDownClosed(object sender, EventArgs e)
{
CheckForTimeSheet();
PopulateTimeSheet();
}
private void dataTimesheet_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
try
{
adapter.Update(tableTS);
}
catch (Exception eX)
{
string eM = "Error on frmTimesheet, dataTimesheet_CellValueChanged";
cError err = new cError(eX, eM);
MessageBox.Show(eM + Environment.NewLine + eX.Message);
}
}
}
No exception occurs, and when I step through the issue seems to be with the SqlCommandBuilder which does NOT build the INSERT / UPDATE / DELETE commands based on my gien SELECT command.
Can anyone see what I am doing wrong?
What am I missing?
You need to set the UpdateCommand instead of SelectCommand on update:
SqlDataAdapter adapter = new SqlDataAdapter();
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
The question is old, but the provided answer by#Anurag Ranjhan need to be corrected.
You need not to write the line:
adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
and enough to write:
SqlDataAdapter adapter = new SqlDataAdapter();
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
//remove the next line
//adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
The Sql update/insert/delete commands are auto generated based on this line
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
You can find the generated update sql by executing the line:
sqlBld.GetUpdateCommand().CommandText;
See the example How To Update a SQL Server Database by Using the SqlDataAdapter Object in Visual C# .NET
The problem said by OP can be checked by reviewing the Sql Statement sent by the client in SQl Server Profiler.

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