I am trying to insert a non specific number of rows from a dataset into a list by using a foreach. But I am unsure how to add a non specific number of items to a list from a dataset.
public void DeviceReset(string r)
{
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText =
"SELECT installation_id FROM masterinstallationmaps WHERE masterinstallation_id = '" + r + "' ";
cmd.ExecuteNonQuery();
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
I am picking out the installation_id from my masterinstallationmap table and if it contains more than 0 rows it should run the foreach to put the rows into the list, otherwise it should run a foreach only inputting 1 item to the list.
List<int> instIdList = new List<int>();
if (ds.Tables[0].Rows.Count > 0)
{
foreach (DataRow row in ds.Tables[0].Rows)
{
//How to insert all rows from the dataset?
}
}
else
{
instIdList.Add(1);
}
The else statement works fine, but nothing happens if the Dataset have more than 0 rows.
I am unsure what to put into the foreach:
foreach (DataRow row in ds.Tables[0].Rows)
{
//How to insert all rows from the dataset?
}
Why can't you just add the value like
foreach (DataRow row in ds.Tables[0].Rows)
{
instIdList.Add(Convert.ToInt32(row["installation_id"]));
}
Related
I fill one combobox with two columns from database with this code:
foreach (DataRow dr2 in dt2.Rows)
{
comboBox1.Items.Add(dr2["Station"].ToString() + " - " + dr2["Ime"].ToString());
}
dbconn.Close();
and combobox look like this:
Now I want to take only first item from this combobox (the numbers) and put into my query for data from database.
I want variable Stations to be with first item from combobox.
I try to get the first index from combobox, but when I debug I see value on the variable is -1 everytime..
The code:
var Stations = comboBox1.SelectedIndex = -1;
MySqlCommand cmd = new MySqlCommand("CALL aladin_surfex.Get_mod_cell_values_meteogram_cell('"+ dtnow +"', " + Stations + ", 5)", dbconn);
MySqlDataAdapter da = new MySqlDataAdapter();
dbconn.Open();
da.SelectCommand = cmd;
DataSet ds = new DataSet();
DataTable dt = new DataTable();
da.Fill(ds);
dt = ds.Tables[0];
foreach (DataRow dr in dt.Rows)
{
dataGridView1.DataSource = dt;
}
dbconn.Close();
I upload a picture from debug mode:
I want variable Stations to be with first item from combobox
Instead of
var stations = comboBox1.SelectedIndex = -1;
use
comboBox1.SelectedIndex = -1;
var stations = comboBox1.SelectedText; // or Text
if I used finalTable.Rows.Add(row.ItemArray) it gives me this error "Input array is longer than the number of columns in this table."
con.Open();
cmd.Connection = con;
cmd.CommandText = "SELECT CustomerName FROM Customers";
SqlDataAdapter adp = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
adp.Fill(ds);
DataTable finalTable = new DataTable();
//finalTable.TableName = "Customers";
if (ds.Tables.Count > 0)
{
int i = 1;
DataTable firstTable = ds.Tables[0];
//firstTable.TableName = "Customers";
foreach (DataRow row in firstTable.Rows)
{
if (i == 5)
{
firstTable.NewRow();
i = 0;
}
finalTable.Rows.Add(row.ItemArray);
i++;
}
}
Repeater1.DataSource = finalTable;
Repeater1.DataBind();
con.Close();
and if i used this finalTable.Rows.Add(row), it gives me "This row already belongs to another table".
con.Open();
cmd.Connection = con;
cmd.CommandText = "SELECT CustomerName FROM Customers";
SqlDataAdapter adp = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
adp.Fill(ds);
DataTable finalTable = new DataTable();
//finalTable.TableName = "Customers";
if (ds.Tables.Count > 0)
{
int i = 1;
DataTable firstTable = ds.Tables[0];
//firstTable.TableName = "Customers";
foreach (DataRow row in firstTable.Rows)
{
if (i == 5)
{
firstTable.NewRow();
i = 0;
}
finalTable.Rows.Add(row);
i++;
}
}
Repeater1.DataSource = finalTable;
Repeater1.DataBind();
con.Close();
}
don't know how to solve it, any solution please?
below is a method that allow you select data from your database by TSQL (select * from table1 ...) then return as datatable and continue processing (eg , bind table)
This is how
1) built a connection string , If you are developing web apps , go to web.config file add below , change parameter according your SQL environment setup.
<configuration>
<connectionStrings>
<add name="PSDatabaseConnectionString" connectionString="Data Source=YourSQLserverName\SQLEXPRESS;Initial Catalog=YourDatabaseName;Integrated Security=True" providerName="System.Data.SqlClient"/>
</connectionStrings>
....
2) then build a method to accept SQL statement and return multiple rows data as datatable . In below code , you do not need to define your datatable column structure , SQL will dynamic built it based on your SQL select statement
public static DataTable RunSQL_DML_FillDataGrid(string TSQL)
{
string connectionString = ConfigurationManager.ConnectionStrings["PSDatabaseConnectionString"].ConnectionString;
SqlDataAdapter dataAdapter;
SqlConnection conn = new SqlConnection(connectionString);
try
{
// Run TSQL on SQL server
dataAdapter = new SqlDataAdapter(TSQL, connectionString);
// MS Term ' Create a command builder to generate SQL update, insert, and
// delete commands based on selectCommand. These are used to
// update the database.
SqlCommandBuilder commandBuilder = new SqlCommandBuilder(dataAdapter);
// Populate a new data table and return the table.
// MS Term ' Populate a new data table and bind it to the BindingSource.
DataTable table = new DataTable();
table.Locale = System.Globalization.CultureInfo.InvariantCulture;
dataAdapter.Fill(table);
return table;
}
catch
{
return null;
}
}
3) Finally , you can bind your data table to other object ( datagridview , datatable ....) . I do not know what object type is Repeater1 inside your code but if it can accept datatable , then it shall bind correctly using the returned datatable
How to use loop to read all records by one click on the button. I have to print many reports.For each row in the table I need to create a report. And read until the last row of the table . My idea is using loop or index table but i don't know how to do it. This is my code:
private void btnin_Click(object sender, RoutedEventArgs e)
{
try
{
cnn.Open();
SqlCommand cmd = new SqlCommand(" SELECT * FROM viewdata1 WHERE Customers = '" + cbbcustomer.Text + "'", cnn);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
cnn.Close();
XtraReport1 report = new XtraReport1();
report.DataSource = dt;
report.ShowPreviewDialog();
}
catch ( Exception ex )
{
MessageBox.Show(ex.Message);
}
}
You could iterate through the Datatable
foreach(DataRow row in dt.Rows)
{
DataTable dtrow = new DataTable();
dtrow = dt.Clone();
dtrow.ImportRow(row);
XtraReport1 report = new XtraReport1();
report.DataSource = dtrow;
//report.ShowPreviewDialog(); Not sure what happens here but maybe a print method is better suited?
}
Basically for each row you create a datatable with the same structure and import one row. Then its assigned as your datasource. This will iterate through all rows.
For some reasons, I had to change something in my code. I used Mark Vance's code but it didn't work:
DataTable a = new DataTable();
a = ((DataView)ctrlgridviewdulieu0.ItemsSource).ToTable();
foreach (DataRow row in a.Rows)
{
DataTable dtrow = new DataTable();
dtrow = a.Clone();
dtrow.ImportRow(row);
try
{
cnn.Open();
SqlCommand cmd = new SqlCommand(" SELECT * FROM viewdulieu2 WHERE Khachdat = N'" + dtrow.ToString() + "'", cnn);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt1 = new DataTable();
da.Fill(dt1);
XtraReport1 report = new XtraReport1();
report.DataSource = dt1;
// report.Print();
cnn.Close();
report.ShowPreviewDialog();
}
catch (Exception ex)
{
cnn.Close();
MessageBox.Show(ex.Message);
}
}
How to remove the duplicate tab page name in C# Windows Form? I tried many times, it still show the duplicate items on the tab page.
Example:
My code:
SqlCommand cmd = new SqlCommand("SELECT type FROM Products ORDER BY type ASC", con);
con.Open();
try
{
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
foreach (DataRow dr in dt.Rows)
{
tabControl1.TabPages.Add(dr["type"].ToString());
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error");
}
con.Close();
var cmd = new SqlCommand("SELECT DISTINCT type FROM Products ORDER BY type ASC", con);
con.Open();
try
{
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
foreach (DataRow dr in dt.Rows)
{
tabControl1.TabPages.Add(dr["type"].ToString());
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error");
}
con.Close();
You can filter out duplicated rows with this function
public DataTable RemoveDuplicateRows(DataTable dataTable, string columnName)
{
Hashtable hashTable = new Hashtable();
ArrayList duplicateList = new ArrayList();
//Add a list of all the unique item values to the hashtable, which in turn stores a combination of key, value pair.
//And add duplicate item value in arraylist.
foreach (var dataRow in dataTable.Rows)
{
if (hashTable .Contains(dataRow[columnName]))
duplicateList.Add(dataRow);
else
hTable.Add(dataRow[columnName], string.Empty);
}
//Removing a list of duplicate items from datatable.
foreach (var dRow in duplicateList)
dataTable.Rows.Remove(dRow);
//Datatable which contains unique records will be return as output.
return dataTable;
}
How to finish the following function which accept three collection parameters for deleted, inserted and updated records and convert the collections to a DataTable for DataAdapter to update the table?
I found a way to convert List to DataTable at How to fill a datatable with List<T>. However, it doesn't set the insert, update and delete flags in DataTable?
void Save(
IEnumerable<int> deleted,
IEnumerable<Poco1> inserted,
IEnumerable<Poco1> updated)
{
var dt = new DataTable();
.... // Initialize dt with deleted, inserted and update?
using (var con = new SqlConnection(ConnectionStr))
{
con.Open();
var da = new SqlDataAdapter("select * from table", con);
da.Update(dt);
}
}
Or is there a better way to update the database table from these three collections? (C# 3.5)
First off, your going to want to also define the Insert, Update and Delete commands:
// Create the other commands.
da.InsertCommand = new SqlCommand("...how to insert");
da.UpdateCommand = new SqlCommand("...how to update");
da.DeleteCommand = new SqlCommand("...how to delete");
Alternatively you can try to use DbCommandBuilder to do it for you at runtime:
// Create the DbCommandBuilder.
DbCommandBuilder builder = factory.CreateCommandBuilder();
builder.DataAdapter = da;
// Get the insert, update and delete commands.
da.InsertCommand = builder.GetInsertCommand();
da.UpdateCommand = builder.GetUpdateCommand();
da.DeleteCommand = builder.GetDeleteCommand();
Next you need to define the DataTables to match the table you are targeting:
DataTable dt = new DataTable();
dt.Columns.Add(add your columns...)
Then you need to add rows to the DataTable, making sure to mark the row as inserted, updated or deleted.
DataRow dr = dt.NewRow();
dr["your column"] = ...
// Don't forget to add the row to the table!
dt.Rows.Add(dr);
// Once the row is added then go ahead and mark it as deleted, modified or new
dr.Delete()
// or
dr.SetAdded();
// or
dr.SetModified();
It wont work the way you are doing , do like this
using (var con = new SqlConnection(ConnectionStr))
{
con.Open();
var da = new SqlDataAdapter("select * from table", con);
var ds=new DataSet();
da.Fill(ds);
var dt= ds.Tables[0];
// all deleted rows
foreach(DataRow dr in dt.Rows.ToList())
{
if(deleted.ToList().Contains((int)dr["id"]))
{
dr.Delete();
}
//all updated rows
foreach(var poco in updated.ToList()
{
DataRow dr = table.Select("id="+poco.id).FirstOrDefault();
dr["field1]=poco.feild1
....set all updated values
}
//all inserted rows
foreach(var poco in inserted.ToList())
{
var dr= dt.NewRow();
dr["id"]=poco.id;
..set all fields
dt.Rows.Add(dr);
}
}
dt.Accept
da.Update(dt);
}