Every time my forms loads/open it will prompt "System.Data.DataRowView", How can I possibly remove this?
Here is my code:
{
InitializeComponent();
GetProcessorCardTypes();
}
private void GetProcessorCardTypes()
{
cn.Open();
MySqlCommand cmd = new MySqlCommand("call GetProcessorMethod(1)", cn);
MySqlDataAdapter adapter = new MySqlDataAdapter(cmd);
DataTable dt = new DataTable();
adapter.Fill(dt);
cmbProcessorMethods.DataSource = dt;
cmbProcessorMethods.ValueMember = "method_id";
cmbProcessorMethods.DisplayMember = "method_name";
}
private void cmbProcessorMethods_SelectedIndexChanged(object sender, EventArgs e)
{
MessageBox.Show(cmbProcessorMethods.SelectedValue.ToString());
}
If you want to completely remove message box, then remove cmbProcessorMethods_SelectedIndexChanged event handler. Or you can change it to display method_name of selected row:
private void cmbProcessorMethods_SelectedIndexChanged(object sender, EventArgs e)
{
DataRowView row = (DataRowView)cmbProcessorMethods.SelectedItem;
MessageBox.Show(row["method_name"].ToString());
}
As Derek pointed, just set DisplayMember and ValueMember properties before assigning data source and your original code will work:
cmbProcessorMethods.ValueMember = "method_id";
cmbProcessorMethods.DisplayMember = "method_name";
cmbProcessorMethods.DataSource = dt;
Related
i have a textbox and listbox in a winform app. when i type a value(i.e,string) in the textbox i want the listbox to show the values from datatable and when i am selecting a particular value from listbox it will display in textbox .
code:
private void txtIName_TextChanged(object sender, EventArgs e)
{
string constring = "Data Source=.;Initial Catalog=Test;User Id=sa;Password=admin#123";
using (SqlConnection con = new SqlConnection(constring))
{
using (SqlCommand cmd = new SqlCommand("SELECT distinct * FROM Item_Details", con))
{
cmd.CommandType = CommandType.Text;
using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
{
using (dt = new DataTable())
{
sda.Fill(dt);
DataView dv = new DataView(dt);
dv.RowFilter = string.Format("IName Like '%{0}%'", txtIName.Text);
listBox1.Visible = true;
listBox1.DataSource = dv;
}
}
}
}
}
but i got the output in listbox like "system.data.datarow". By debugging i can seen that rows which i want, in dataview 'dv'. what i am missing here? thanks.
You don't need to load data each time the TextChanged event fires. It's enough to load data in Load event of your form and then in TextChanged just filter the data. Then using an event like DoubleClick of ListBox set the text of TextBox:
private DataTable dataTable = new DataTable();
private void Form1_Load(object sender, EventArgs e)
{
string constring = #"Data Source=.;Initial Catalog=Test;User Id=sa;Password=admin#123";
using (SqlConnection con = new SqlConnection(constring))
{
using (SqlDataAdapter sda = new SqlDataAdapter("SELECT distinct * FROM Item_Details", con))
{
sda.Fill(dataTable);
}
}
this.listBox1.DataSource = new DataView(dataTable);
this.listBox1.DisplayMember = "IName";
this.listBox1.Visible = false;
}
private void txtIName_TextChanged(object sender, EventArgs e)
{
var dv = (DataView)this.listBox1.DataSource;
dv.RowFilter = string.Format("IName Like '%{0}%'", txtIName.Text);
listBox1.Visible = true;
}
private void listBox1_DoubleClick(object sender, EventArgs e)
{
var item = (DataRowView)listBox1.SelectedItem;
if (item != null)
this.txtIName.Text = item["IName"].ToString();
else
this.txtIName.Text = "";
this.listBox1.Visible = false;
}
Don't forget to attach Form1_Load, txtIName_TextChanged and listBox1_DoubleClick handlers to events.
You must specify your DisplayMember, it must be some Field in your DataView
listBox1.DisplayMember = "Your Field"
then you can suscribe to the event SelectedValueChanged :
listBox1.SelectedValueChanged += new EventHandler(listBox1_SelectedValueChanged);
visual studio create for you an event handler
void listBox1_SelectedValueChanged(object sender, EventArgs e)
{
// you get your selected item here
}
hope it helps
I'm new in this and I'm a little lost.
Trying to show the values of my database in textbox by selecting in the combobox. But I can't.
Please help me. This is my code:
private void CargarDatos()
{
string consulta = "SELECT * FROM [dbo].[alumno]";
DataTable dt = new DataTable();
SqlConnection con = new SqlConnection(Properties.Settings.Default.conexion);
SqlCommand cmd = new SqlCommand(consulta, con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
try
{
con.Open();
da.Fill(dt);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
con.Close();
this.dataGridView1.DataSource = dt;
cbalumno.DataSource = dt;
cbalumno.DisplayMember="Nombre";
cbalumno.ValueMember="Id";
}
private void Form1_Load(object sender, EventArgs e)
{
CargarDatos();
}
private void cbalumno_SelectedIndexChanged(object sender, EventArgs e)
{
}
}
}
The parameters that i want to show are "Name" "Surname" and "DNI" of the table alumno.
Any ideas to how can I do that??
You can use DataRowView to get the record being bound with current SelectedItem. The Row property of DataRowView object will give you data row. Using this row you can get the columns being bound to it.
private void cbalumno_SelectedIndexChanged(object sender, EventArgs e)
{
DataRowView vrow = (DataRowView)cbalumno.SelectedItem;
string sValue = vrow.Row["Name"].ToString();
}
You already have placed the event cbalumno_SelectedIndexChanged in your code and now you have to use it.
Inside that event, just use the Text peroperty of that textbox and assign the value of the selected item in your combo box like this :
private void cbalumno_SelectedIndexChanged(object sender, EventArgs e)
{
yourTextBoxID.Text = comboBoxID.Text;
}
Hope this helps.
I wanna fill grid with a background worker but I don't know where I must add DataGrid.DataSource=DataTable; is there any simple example that explain how can I use background worker for filling DataGrid?
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
setgride();
}
private void setgride()
{
string constring = "constring";
SqlCommand com = new SqlCommand();
SqlConnection con = new SqlConnection(constring);
com.Connection = con;
com.CommandText = " select * from Request";
SqlDataAdapter adapt = new SqlDataAdapter(com);
DataTable dt2 = new DataTable();
adapt.Fill(dt2);
propdt2 = dt2;
}
private void button1_Click(object sender, EventArgs e)
{
this.backgroundWorker1.RunWorkerAsync();
}
in BackgroundWorker.RunWorkerCompleted Event , handle this event and assign source property here.
I want to populate TWO dropdownlist, based on selection of first dropdownlist the second dropdownlist will get populated.
Example :
Like i have two dropdownlist namely 1.ddlCountry and 2.ddlState
Now when country is selected then depending on the selected Country the States related with that Country will get populated in the State dropdownlist. I want to achieve this withour reloading the whole page in Asp.Net with coding language as C#.
How can i achieve the same?
Dropdownlist is fetching data from database by executing query.
You can use AJAX toolkit CascadingDropDown as told by Naresh.
OR
use ajax update panel and keep all Dropdowns in it. So the whole page will not load on changing dropdown value.
You didnt give the code to further solution.
protected void ddlCountry_SelectedIndexChanged(object sender, EventArgs e)
{
FillStateByCountry();
}
protected void ddlState_SelectedIndexChanged(object sender, EventArgs e)
{
FillLocationByCountryandState();
}
private void FillStateByCountry()
{
DataSet dstFillState;
int CountryId = Convert.ToInt32(ddlCountry.SelectedValue.ToString());
dstFillState = Tbl_State.FillDDLState(CountryId);
ddlState.DataSource = dstFillState;
ddlState.DataTextField = "State";
ddlState.DataValueField = "Id";
ddlState.DataBind();
}
similarly FillLocationByCountryandState();
Add two dropdownlists to your form and name it as cmbStates, cmbCities
when you select state name from cmbStates(dropwdownlist), cmbCities(dropdownlist) generates cities based on state name(cmbStates)
by fetching data from database
private void Form1_Load(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection("server=pbs-server;database=p2p;user id=shekar;password=sekhar#1346");
SqlCommand cmd = new SqlCommand("select states from Country", con);
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(cmd);
con.Open();
da.Fill(ds, "Country");
cmbStates.DataSource = ds.Tables[0];
cmbStates.SelectedValue = 0;
con.Close();
}
private void cmbStates_SelectedIndexChanged(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection("server=xxxx;database=xxxx;user id=xxxxr;password=xxxxxx");
SqlCommand cmd = new SqlCommand("select cities from States where cityname = 'cmbStates.SelectedItem.ToString()'", con);
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(cmd);
con.Open();
da.Fill(ds, "States");
cmbCities.DataSource = ds.Tables[0];
cmbCities.SelectedValue = 0;
con.Close();
}
OR
manually adding items
namespace DropDownlist
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
cmbStates.Items.Add("Andhra Pradesh");
cmbStates.Items.Add("Tamilnadu");
cmbStates.Items.Add("Karnataka");
cmbStates.SelectedValue = 0;
}
private void cmbStates_SelectedIndexChanged(object sender, EventArgs e)
{
if (cmbStates.SelectedItem.ToString() == "Andhra Pradesh")
{
cmbCities.Items.Clear();
cmbCities.Items.Add("Hyderabad");
cmbCities.Items.Add("Guntur");
cmbCities.Items.Add("Vijayawada");
cmbCities.SelectedValue = 0;
}
else if (cmbStates.SelectedItem.ToString() == "Tamilnadu")
{
cmbCities.Items.Clear();
cmbCities.Items.Add("Chennai");
cmbCities.Items.Add("Coimbatore");
cmbCities.Items.Add("ooty");
cmbCities.SelectedValue = 0;
}
else if (cmbStates.SelectedItem.ToString() == "Karnataka")
{
cmbCities.Items.Clear();
cmbCities.Items.Add("Bangalore");
cmbCities.Items.Add("Mangalore");
cmbCities.SelectedValue = 0;
}
else
{
MessageBox.Show("Please Select any value");
}
}
}
}
I am making windows application and am stuck at one place.
My problem is that i want to display record in a DataGridView by selecting a ComboBox item but I do not understand the proper way to do it. Please help me in overcome this problem.
private void grid_Load(object sender, EventArgs e)
{
con = new SqlConnection(constr);
try
{
con.Open();
//this.studTableAdapter.Fill(this.pRJTestDBDataSet.stud);
//above line show error for connection to database
da = new SqlDataAdapter("SELECT stud_no FROM stud", con);
DataTable dt = new DataTable();
da.Fill(dt);
comboBox1.DataSource = dt;
comboBox1.DisplayMember = "stud_no";
comboBox1.ValueMember = "stud_no";
comboBox1.DataSource = dt;
comboBox1.SelectedIndex = -1;
comboBox1_SelectedIndexChanged(sender, e);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{ con.Close(); }
}
private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
this.studTableAdapter.Fill(pRJTestDBDataSet.stud);
//above line show error for connection to database
}
i have tried above code but its not working there error like login fail to user
cmd = new SqlCommand("SELECT stud_no FROM stud", con);
da = new SqlDataAdapter(cmd);
da.Fill(dt);
Combobox1.DataSource = dt;
Combobox1.DisplayMember = dt.Columns("Stud_no").ToString;
rebind the DataGrid at each SelectedItemIndex change event of Combo Box by the data you want to bind.
private void button2_Click(object sender, EventArgs e)//button 2 is a show data button
{
if (combo_floor.Text != "")
{
DataSet ds = new DataSet();
string sql = "select floor_id,floor_no,floor_remark,floor_entrydate from Floorinfo where floor_no='"+combo_floor.Text+"'";
ds = c.select_query(sql);
dataGridView1.DataSource = ds.Tables["a"];
combo_floor.Text = "";
}
else
{
showdata();
//showdata()is made for show all data from the given table name
}
}
//connection is in different class so please dont mind