how to fill DropDownList from database in asp.net ?
and when i pick value from the DropDownList how to catch this event ?
Conn.Open();
SQL = "SELECT distinct city FROM MEN";
dsView = new DataSet();
adp = new SqlDataAdapter(SQL, Conn);
adp.Fill(dsView, "MEN");
adp.Dispose();
DropDownList1. ?????? (what do to ?)
thanks in advance
You set the DataSource, DataTextField and DataValueField and call DataBind() in order to populate the dropdownlist.
The datasource can be pretty much any IEnumerable and the text and value will be looked up with reflection.
The event you want to catch is the SelectedIndexChanged event - this will fire when you change the selection.
First take the details in a dataset
then the following code will help you:
DropDownList1.DataSource = ds
DropDownList1.DataTextField = "emailid"
DropDownList1.DataValueField = "userid"
DropDownList1.DataBind()
DropDownList1.Items.Insert(0, New ListItem("select", "-1"))
Simple sample code :
DropDownList.DataSource = yourDataSource;
DropDownList.DataTextField = "displayNameColumnName ";
DropDownList.DataValueField = "TheValueColumnName";
DropDownList.DataBind();
This could be a complete walkthrough for you in this case :
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
BindDropDownLists();
}
}
protected void Page_Init(object sender, EventArgs e)
{
SqlDataSource sqlDS = new SqlDataSource();
sqlDS.ConnectionString = ConfigurationManager.ConnectionStrings[0].ToString();
sqlDS.SelectCommand = "select GenderID,Gender from mylookupGender";
form1.Controls.Add(sqlDS);
DropDownList ddl = new DropDownList();
ddl.ID = "dddlGender";
ddl.DataSource = sqlDS;
ddl.DataTextField = "Gender";
ddl.DataValueField = "GenderID";
form1.Controls.Add(ddl);
// ... Repeat above code 9 times or put in a for loop if they're all the same...
}
private void BindDropDownLists()
{
foreach (Control ctl in form1.Controls)
{
if (ctl is DropDownList)
{
(ctl as DropDownList).DataBind();
}
}
}
//...Wrote separate class for calling this function
FunctionClass obj = new FunctionClass();
List<Designation> details = new List<Designation>();
bool result1 = obj.DataDrop(out details);
if (result1 == true)
{
dropDownDesignation.DataSource = details;
dropDownDesignation.DataTextField = "designation";
dropDownDesignation.DataValueField = "Designation_ID";
dropDownDesignation.DataBind();
dropDownDesignation.Items.Insert(0, new ListItem("--Select--", "0"));
}
//..This function wrote inside FunctionClass and called from aspx.cs page
public bool DataDrop(out List<Designation> designationDetails)
{
designationDetails = new List<Designation>();
conn = new SqlConnection(connectionName);
conn.Open();
command.Connection = conn;
command.CommandType = CommandType.StoredProcedure;
command.CommandText = "DesignationDetails";
userReader = command.ExecuteReader();
if(userReader.HasRows)
{
while(userReader.Read())
{
designationDetails.Add(new Designation()
{
designationId=userReader.GetInt32(0),
designation=userReader.GetString(1)
});
}
}
return true;
}
//..This should declare outside the class but inside the namespace
public class Designation
{
public int designationId { get; set; }
public string designation { get; set; }
}
Another way to bind dropdownlist is...
<asp:DropDownList ID="ddlCity" runat="server" DataValueField="pkId" DataTextField="cityName" DataSourceID="sqlDB">
</asp:DropDownList>
<asp:SqlDataSource ID="sqlDB" ConnectionString='$Name of connecitonstring' runat="server" SelectCommand="Select * from tbl_City"></asp:SqlDataSource>
Related
This is my code to display table value to a DropDownList.
using (SqlConnection con = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["Conn"].ConnectionString))
{
con.Open();
string str="SELECT ItemOne,ItemTwo,ItemThree FROM tableItem";
using (SqlCommand cmd = new SqlCommand(str, con))
{
SqlDataAdapter dA=new SqlDataAdapter(cmd);
dA.Fill(dT);
DropDownList1.DataSource = dT;
DropDownList1.DataValueField = "ItemTwo";
DropDownList1.DataTextField = "ItemOne";
DropDownList1.DataBind();
}
This is to display the selected value of DropDownList to a TextBox.
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
TextBox1.Text = DropDownList1.SelectedValue.ToString();
TextBox2.Text = //Get the value of ItemThree here
}
My problem is: How will I display the column value of ItemThree in another TextBox.
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
TextBox1.Text = DropDownList1.SelectedValue.ToString();
TextBox2.Text = DropDownList1.Items[2].ToString(); // 2 is your index
}
Another way of doing this
var connectionString = ConfigurationManager.ConnectionStrings["Conn"].ConnectionString;
var sql = "SELECT ItemOne, ItemTwo, ItemThree FROM tableItem";
using (var table = new DataTable) {
using (var adapter = new SqlDataAdapter(sql, connectionString)
adapter.Fill(table);
foreach (DataRow dr in table.Rows)
DropDownList1.Items.Add(new ListItem(dr["ItemTwo"], dr["ItemTwo"]) {
Tag = dr["ItemThree"]
});
}
Then from the event handler
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
TextBox1.Text = DropDownList1.SelectedValue.ToString();
TextBox2.Text = DropdownList1.SelectedItem.Tag.ToString();
}
I worked on asp web page that have a dropdown of semester names, and according to the selected item from this dropdown a gridview of levels and courses will appear.
The problem is that grid view never change according to the drop down selection
So when i choose a semester name let's say "Fall", the gridview shows all semesters " Fall & Spring & Summer" with their levels and courses.
Here is my code:
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
gvSemester.DataSource = GetData(string.Format("select COURSE_SEMESTER from COURSE GROUP BY COURSE_SEMESTER"));
gvSemester.DataBind();
}
}
private static DataTable GetData(string query)
{
string constr = ConfigurationManager.ConnectionStrings["ConnectionString2"].ConnectionString;
using (OracleConnection con = new OracleConnection(constr))
{
using (OracleCommand cmd = new OracleCommand())
{
cmd.CommandText = query;
using (OracleDataAdapter sda = new OracleDataAdapter())
{
cmd.Connection = con;
sda.SelectCommand = cmd;
using (DataSet ds = new DataSet())
{
DataTable dt = new DataTable();
sda.Fill(dt);
return dt;
}
}
}
}
}
protected void Show_Hide_LevelsGrid(object sender, EventArgs e)
{
ImageButton imgShowHide = (sender as ImageButton);
GridViewRow row = (imgShowHide.NamingContainer as GridViewRow);
if (imgShowHide.CommandArgument == "Show")
{
row.FindControl("pnlLevels").Visible = true;
imgShowHide.CommandArgument = "Hide";
imgShowHide.ImageUrl = "~/image/minus.png";
string semesterId = gvSemester.DataKeys[row.RowIndex].Value.ToString();// semester
GridView gvLevel = row.FindControl("gvLevel") as GridView;
BindLevels(semesterId, gvLevel);
}
else
{
row.FindControl("pnlLevels").Visible = false;
imgShowHide.CommandArgument = "Show";
imgShowHide.ImageUrl = "~/image/plus.png";
}
}
private void BindLevels(string semesterId, GridView gvLevel)
{
gvLevel.ToolTip = semesterId;
gvLevel.DataSource = GetData(string.Format("SELECT COURSE_LEVEL from COURSE where COURSE_SEMESTER= '" + semesterId + "' GROUP BY COURSE_LEVEL ORDER BY COURSE_LEVEL")); //was COURSE_SEMESTER=Check it shows the selected semester levels for all
gvLevel.DataBind();
}
protected void Show_Hide_CoursesGrid(object sender, EventArgs e)
{
ImageButton imgShowHide = (sender as ImageButton);
GridViewRow row = (imgShowHide.NamingContainer as GridViewRow);
if (imgShowHide.CommandArgument == "Show")
{
row.FindControl("pnlCourses").Visible = true;
imgShowHide.CommandArgument = "Hide";
imgShowHide.ImageUrl = "~/image/minus.png";
string levelId = (row.NamingContainer as GridView).DataKeys[row.RowIndex].Value.ToString();//level
GridView gvCourse = row.FindControl("gvCourse") as GridView;//..
BindCourses(levelId, gvCourse);//..
}
else
{
row.FindControl("pnlCourses").Visible = false;
imgShowHide.CommandArgument = "Show";
imgShowHide.ImageUrl = "~/image/plus.png";
}
}
private void BindCourses(string levelId, GridView gvCourse)
{
gvCourse.ToolTip = levelId;
gvCourse.DataSource = GetData(string.Format("select * from COURSE where COURSE_LEVEL='{0}'", levelId));
gvCourse.DataBind();
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
}
}
You can set your dropdown list AutoPostBack = True.
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
BindLevels();
}
fill your gridview with dropdown SelectedIndexChanged event and apply where condition in your SQL query.
Add Update Panel for the "levels and courses" grid.
At the dropdown Change event , you update the grid.
UpdatePanelId.Update();
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 have two dynamically populated radio button lists. The first one gets populated on a button click, the other one on the change event of the first radio button list. The problem is only with the second list. The issue is that I am not able to retrieve the changed value of the second radio button list in the InsertButton_Click method(marked by **). It always returns the default index value i.e 0. I don't have anything in page_load event. I read quite a few similar questions but none seem to help. Please guide. Below is the asp and c# code for the same:
ASP:
<asp:Button id="SaveButton"
Text="Save"
runat="server" onclick="SaveButton_Click">
</asp:Button>
<asp:Button id="VisualiseButton"
Text="Visualise"
runat="server" onclick="VisualiseButton_Click">
</asp:Button>
<!--<hr />-->
<asp:RadioButtonList id="RadioButtonList2" runat="server" Visible="false"
onselectedindexchanged="RadioButtonList2_SelectedIndexChanged" ></asp:RadioButtonList>
<asp:RadioButtonList id="RadioButtonList1" runat="server" Visible="false" ></asp:RadioButtonList>
<asp:Button id="SaveToDBButton"
Text="Insert"
runat="server" Visible="false" onclick="InsertButton_Click">
C#:
protected void SaveButton_Click(object sender, EventArgs e)
{
String selQuery = "SELECT id, name FROM categories";
try
{
con.Open();
SqlDataAdapter da = new SqlDataAdapter(selQuery, con);
DataTable dt = new DataTable();
da.Fill(dt);
RadioButtonList2.DataSource = dt;
RadioButtonList2.DataTextField = "name";
RadioButtonList2.DataValueField = "id";
RadioButtonList2.DataBind();
RadioButtonList2.RepeatColumns = 3;
RadioButtonList2.AutoPostBack = true;
RadioButtonList2.Visible = true;
}
catch (SqlException ex)
{
}
finally
{
if (con != null)
{
con.Close();
}
}
}
protected void RadioButtonList2_SelectedIndexChanged(object sender, EventArgs e)
{
String catId = RadioButtonList2.SelectedValue;
SqlCommand cmdselect = new SqlCommand("SELECT DISTINCT categoryId, linkTablesCategories.tableName, tableDescription FROM linkTablesCategories, tableDescriptions where linkTablesCategories.tableName = tableDescriptions.tableName and categoryId ='" + catId + "'");
RadioButtonList1.Items.Clear();
try
{
con.Open();
cmdselect.Connection = con;
SqlDataReader dar = cmdselect.ExecuteReader();
if (dar.HasRows)
{
while (dar.Read())
{
ListItem li = new ListItem(dar["tableName"].ToString(), dar["categoryId"].ToString());
li.Attributes.Add("title", dar["tableDescription"].ToString());
RadioButtonList1.Items.Add(li);
}
}
RadioButtonList1.Visible = true;
SaveToDBButton.Visible = true;
}
catch (SqlException ex)
{
//lblMessage.Text = ex.Message;
}
finally
{
cmdselect.Dispose();
if (con != null)
{
con.Close();
}
}
}
protected void InsertButton_Click(object sender, EventArgs e)
{
String tableId="";
**tableId = RadioButtonList1.SelectedItem.Text;**
String path = Server.MapPath("~/");
string filepath = path + Session["filepath"].ToString();
StreamReader sr = new StreamReader(filepath);
string line = sr.ReadLine();
string[] value = line.Split(',');
DataTable dt = new DataTable();
DataRow row;
foreach (string dc in value)
{
dt.Columns.Add(new DataColumn(dc));
}
while (!sr.EndOfStream)
{
value = sr.ReadLine().Split(',');
if (value.Length == dt.Columns.Count)
{
row = dt.NewRow();
row.ItemArray = value;
dt.Rows.Add(row);
}
}
SqlBulkCopy bc = new SqlBulkCopy(con.ConnectionString, SqlBulkCopyOptions.TableLock);
bc.DestinationTableName = tableId;
bc.BatchSize = dt.Rows.Count;
con.Open();
bc.WriteToServer(dt);
bc.Close();
con.Close();
}
it was with the line:
ListItem li = new ListItem(dar["tableName"].ToString(), dar["categoryId"].ToString());
The categoryId was a constant value and thus the issue, again my bad.
Thanks
i have a simple question
i have a form which contain two related combo boxes but i have problem in updating the second dropdown content
this is the code
private void DiaryForm_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'expensesDataSet.Item' table. You can move, or remove it, as needed.
// this.itemTableAdapter.Fill(this.expensesDataSet.Item);
using (OleDbConnection con = dbconn.dbconnection())
{
ds1 = new ExpensesDataSet();
string sql = "SELECT * From DiaryView";
da = new System.Data.OleDb.OleDbDataAdapter(sql, con);
da.Fill(ds1, "DiaryView");
NavigateRecords();
MaxRows = ds1.Tables["DiaryView"].Rows.Count;
//fill category combobox
string sqlcat = "SELECT * From Category";
catda = new System.Data.OleDb.OleDbDataAdapter(sqlcat, con);
catda.Fill(ds1, "Category");
catda.Update(ds1, "Category");
comboBox2.DataSource=ds1.Tables["Category"];
comboBox2.DisplayMember = "cat_name";
comboBox2.ValueMember="cat_id";
//comboBox1.Enabled = false;
}
}
private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
{
using (OleDbConnection con = dbconn.dbconnection())
{
if (comboBox2.Items.Count > 0)
{
{
string cat = comboBox2.SelectedValue.ToString();
comboBox1.Enabled = true;
int catid = int.Parse(comboBox2.SelectedValue.ToString());
string sqlitem = "SELECT * From Item where cat_id = " + catid;
catda = new System.Data.OleDb.OleDbDataAdapter(sqlitem, con);
this.itemBindingSource.EndEdit();
catda.Fill(ds1, "Item");
catda.Update(ds1, "Item");
comboBox1.DataSource = ds1.Tables["Item"];
comboBox1.DisplayMember = "item_name";
comboBox1.ValueMember = "item_id";
}
}
}
}
there is two tables:
category(cat_id,cat_name)
item(item_id,item_name,cat_id)
what can i do??
plz help :)
If you want to clear the combobox, just do:
combobox1.Items.Clear();
It's as easy as that.