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Asp.Net C# Delete row from dataTable gridview on button click

I'm displaying a datatable that selects a number of elements from the database (IncomingsId, Type, Cost, Frequency) and I'm not sure how to delete a row when a button is clicked.
I've tried many solutions so far but nothing is working.
Here is the button I have within my Grid view
<asp:TemplateField HeaderText="Delete">
<ItemTemplate>
<asp:button id="DeleteRowButton" text="Delete Record" onclick="DeleteRowButton_Click" runat="server"/>
</ItemTemplate>
</asp:TemplateField>
And here is the code behind this page were I am creating the datatable.
SqlConnection con;
public _Default()
{
con = new SqlConnection(#"MySQLConnection");
}
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
DisplayRecord();
}
}
public DataTable DisplayRecord()
{
string userId = (HttpContext.Current.User.Identity.GetUserId());
SqlDataAdapter Adp = new SqlDataAdapter("select * from Incomings where AspNetUsersId = '" + userId +"'", con);
DataTable Dt = new DataTable();
Dt.AcceptChanges();
Adp.Fill(Dt);
grid1.DataSource = Dt;
grid1.DataBind();
return Dt;
}
public void DeleteRowButton_Click(object sender, EventArgs e)
{
}
Cheers in advance for any help. I'm sure it's a simple resolution

You need a way for your code to know which ID to delete. Here is how I would normally do it:
Replace your button with an ItemTemplate, and add the button in here instead:
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:Button Text="Delete" runat="server" CommandArgument='<%# Eval("userId") %>' CommandName="Delete" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
When you have the button this way, you now have access to a CommandArgument and CommandName attributes. Notice the argument I am passing is Eval("userId"), the command name (as you will see later) is used to recognize what action you want to execute (this could be anything, is just a name).
Replace the CommandArgument with whatever value(s) you want to pass to the server, using the name that came from the database/datasource (I am guessing it would be userId).
Then, to capture this you need to implement the RowCommand event of the GridView, and intercept the correct CommandName:
public void GridView1_RowCommand(Object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "Delete")
{
string userId = e.CommandArgument.ToString();
//do something with the id
}
}
Here you have to make sure the CommandName in your button, matches to whatever action you want to execute in the RowCommand. This should do the trick.
Don't forget to bind the event to your GridView:
<asp:GridView OnRowCommand="GridView1_RowCommand" ID="GridView1" runat="server">
...
</asp:GridView>

just use this for the front-end code
<asp:GridView ID="grid1" OnRowDeleting="OnRowDeleting" DataKeyNames="deleteR" runat="server" AutoGenerateColumns="False" CellPadding="4" GridLines="None" style="width:100%" >
<columns>
<asp:TemplateField HeaderText="Delete Row">
<ItemTemplate>
<asp:Button ID="btnDelete" runat="server" class="btn btn-primary" Text="Delete" CommandName="Delete" OnRowDataBound="OnRowDataBound" />
</ItemTemplate>
</asp:TemplateField>
And have this in behind it:
protected void OnRowDeleting(object sender, GridViewDeleteEventArgs e)
{
int deleteR= Convert.ToInt32(grid1.DataKeys[e.RowIndex].Values[0]);
//have a sql statement here that add's the parameter ID for the row you want to delete, something like
SqlCommand com = new SqlCommand ("Delete FROM yourdatabase Where yourID = #yourID"
com.Parameters.AddWithValue("#yourID", yourID)
}

What you're looking for is indeed a simple solution.
You can use a foreach loop to search all DataRows within the DataTable for some kind of ID.Here's an example of what I mean:
String s = "/* IncomingsId for what you want to delete */";
foreach (DataRow r in dt.Rows) {
if (r["IncomingsId"].ToString().Equals(s)) {
dt.Rows.Remove(r);
}
}

Just a quick update for anyone that's helped me, thanks for your advice.
Asp.Net has it's own built in AutoGenerateDeleteButton and I set that to true and ran a bit of code behind it.
A simple solution that really shouldn't have taken me all day to complete!

gridview can't add after clearing

I am using entity framework and taking my datas from database and fill my gridview with them.Datas selected by user from a treview.Simply, user selects a data from treeview and I put it to gridview. Lastly I have a button for clearing the gridview. Here is my aspx:
<div id="divPrint" style="background-color: white" runat="server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<p style="text-align:center">HDCVI KAMERA FİYAT TEKLİFİDİR</p>
<asp:GridView ID="GridViewHdcvi" runat="server" DataSourceID="EntityDataSourceHdcvi" AutoGenerateColumns="False">
<Columns>
<asp:TemplateField HeaderText="ÜRÜN VE DETAYLARI">
<ItemStyle Width="400px" />
<ItemTemplate>
<div style="color: red" class="text-center"><%#Eval("UrunAdi") %></div>
<%#Eval("UrunDetay") %>
</ItemTemplate>
</asp:TemplateField>
<asp:ImageField HeaderText="ÜRÜN GÖRSELİ" DataImageUrlField="UrunResim"></asp:ImageField>
<asp:TemplateField HeaderText="BİRİM FİYAT">
<ItemTemplate>
<%#Eval("UrunFiyati") %>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="ADET">
<ItemTemplate>
<asp:TextBox ID="txtAdet" runat="server" Width="40px"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
</div>
<asp:Button ID="btnListiSifirla" runat="server" Text="Listeyi Sıfırla" CssClass="btn btn-danger" OnClick="btnListiSifirla_Click" />
And my codebehind:
static List<string> urunList = new List<string>();
protected void TreeView1_SelectedNodeChanged(object sender, EventArgs e)
{
string id = TreeView1.SelectedValue;
urunList.Add(id);
listeyiDoldur();
}
protected void listeyiDoldur()
{
if (urunList.Count == 0)
{
failDiv.Visible = true;
}
else
{
string query = "SELECT UrunTable.UrunAdi, UrunTable.UrunFiyati, UrunTable.UrunResim, UrunTable.UrunKategori, UrunTable.UrunDetay FROM UrunTable WHERE ";
foreach (var val in urunList)
{
if (val.Equals(urunList[urunList.Count - 1]))
{
query += "UrunTable.UrunId = " + val;
}
else
{
query += "UrunTable.UrunId = " + val + " || ";
}
}
EntityDataSourceHdcvi.CommandText = query;
divPrint.Visible = true;
btnListiSifirla.Visible = true;
}
}
protected void btnListiSifirla_Click(object sender, EventArgs e)
{
urunList.Clear();
btnListiSifirla.Visible = false;
Page_Load(null,EventArgs.Empty);
}
I can successfully display selected datas in gridview and clear them when button is pressed. Here is the problem: After clearing the gridview I can't add the last added item again.For example if I add item1,item2 and item3 in this order,after clearing the gridview I can't add item3. I can add item1 or item2, then item3. I can't add item firstly which I added last before clearing. I tried clearing gridview in button's onClick and tried other lots of things but nothing gave any result. Thanks for your time.

Creating the quantity update button for Cart System in ASP.NET

I am creating the update button for the cart system in asp.net. What am I trying to do is to allow user key in the quantity items and then click the update button. Here is the design of the shopping cart system...
Unfortunately the update button doesn't work properly after the first row. I have debugged the problem and the for loop inside the btn_update_Click method returns the value of zero.
Is there any other way to overcome the problem? Thanks
Here is the source code:
<b><asp:Label ID="lbl_showResult" runat="server" Text=""></asp:Label></b>
<asp:GridView ID="grv_cart" runat="server" AllowPaging="True" AutoGenerateColumns="False" DataSourceID="sds_store" ShowHeader="True" GridLines="None" CssClass="table">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<a class="hyp_productimage imgLiquidFill imgLiquid productImage img-responsive" href='<%# string.Format("product.aspx?ProductID={0}", Eval("product_id")) %>'>
<img src='<%#Eval("image") %>' />
</a>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Product">
<ItemTemplate>
<asp:Hyperlink ID="hyp_productname" Text='<%# Eval("product_name") %>' runat="server" NavigateUrl='<%# string.Format("product.aspx?ProductID={0}", Eval("product_id")) %>'></asp:Hyperlink>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox ID="txt_productQuantity" Text='<%# Eval("product_quantity") %>' CssClass="form-control" runat="server" Width="60" MaxLength="5"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<ItemTemplate>
<asp:Button ID="btn_update" Text="Update" runat="server" CommandArgument='<%# Eval("id") %>' CssClass="btn btn-warning" OnClick="btn_update_Click" />
<asp:Button ID="btn_remove" Text="Delete" runat="server" CommandArgument='<%# Eval("id") %>' CssClass="btn btn-danger" onclick="btn_remove_Click"/>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Cost">
<ItemTemplate>
<asp:Hyperlink ID="hyp_productcost" Text='<%#"$"+Eval("product_cost") %>' runat="server" NavigateUrl='<%# string.Format("product.aspx?ProductID={0}", Eval("product_id")) %>'></asp:Hyperlink>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="sds_store" runat="server"
ConnectionString="<%$ ConnectionStrings:websiteConnection %>"
SelectCommand="SELECT [id], [product_id], [product_name], [product_cost], [product_description], [product_quantity], [image], [date] FROM [tbl_cart] WHERE [name] = #username AND [visible] = #visible">
<SelectParameters>
<asp:sessionparameter sessionfield="login" Name="username" />
<asp:Parameter Name="visible" Type="string" DefaultValue="true" />
</SelectParameters>
</asp:SqlDataSource>
<h4><asp:Label ID="lbl_totalCost" Text="" runat="server" CssClass="pull-right"></asp:Label></h4>
<br /><br /><br />
<asp:Button ID="btn_buy" Text="Buy Now" runat="server" CssClass="btn btn-success btn-lg pull-right" OnClick="btn_buy_Click" />
Here's another source code for the .cs:
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data.SqlClient;
using System.Diagnostics;
using System.Linq;
using System.Text.RegularExpressions;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace websiteEcom
{
public partial class cart : System.Web.UI.Page
{
// Open the connection for the sql
private static SqlConnection conn;
private static SqlCommand command;
protected void Page_Load(object sender, EventArgs e)
{
// Create an instance for the connection of database
string connectionString = ConfigurationManager.ConnectionStrings["websiteConnection"].ToString();
conn = new SqlConnection(connectionString);
command = new SqlCommand("", conn);
// Checks how many items are there inside the cart database and display it to the label
CheckHowManyItem();
// Multiply all the sums of the cost
lbl_totalCost.Text = "Total Cost: $"+TotalProductCost().ToString();
}
// Checks how many items are there inside the cart database and display it to the label
public void CheckHowManyItem()
{
try
{
conn.Open();
// Retrieve the number of rows from the database
string query = string.Format("SELECT COUNT(*) FROM tbl_cart WHERE name = '{0}' AND visible = '{1}'", Session["login"], "true");
command.CommandText = query;
int numberOfItems = (int)command.ExecuteScalar();
// If the number of rows is zero
if (numberOfItems == 0)
{
lbl_showResult.Text = "You have no items inside the cart.";
btn_buy.Visible = false;
}
else
{
// If there is number of rows inside
lbl_showResult.Text = "There are currently " + numberOfItems + " inside the cart.";
btn_buy.Visible = true;
}
}
finally
{
conn.Close();
}
}
protected void btn_remove_Click(object sender, EventArgs e)
{
// Get the value from the button ASP.NET gridview
Button btn = (Button)sender;
try
{
conn.Open();
// Make the cart invisible if the id matches with the grid view data source
string query = string.Format("UPDATE tbl_cart SET visible = '{0}' WHERE id = '{1}'", "false", btn.CommandArgument);
command.CommandText = query;
command.ExecuteNonQuery();
Response.Redirect("cart.aspx");
}
finally
{
conn.Close();
}
}
// Multiply all the values of purchases together
public int TotalProductCost()
{
int totalCost = 0;
int currentCost = 0;
int currentQuantity = 0;
for (int i = 0; i < grv_cart.Rows.Count; i++)
{
// Get the data values from the forms
HyperLink hypCost = (HyperLink)grv_cart.Rows[i].Cells[0].FindControl("hyp_productcost");
TextBox txtQuantity = (TextBox)grv_cart.Rows[i].Cells[0].FindControl("txt_productQuantity");
// Sum the product quantity and the product cost
// Attempt to parse your value (removing any non-numeric values)
currentQuantity = Int32.Parse(Regex.Replace(txtQuantity.Text, #"[^\d]", ""));
// Attempt to parse your value (removing any non-numeric values)
currentCost = Int32.Parse(Regex.Replace(hypCost.Text, #"[^\d]", ""));
currentCost *= currentQuantity;
totalCost += currentCost;
}
return totalCost;
}
protected void btn_buy_Click(object sender, EventArgs e)
{
}
protected void btn_update_Click(object sender, EventArgs e)
{
// Get the value from the button ASP.NET gridview
Button btn = (Button)sender;
foreach (GridViewRow grvCart in grv_cart.Rows)
{
Debug.WriteLine(btn.CommandArgument);
TextBox textQuantity = (TextBox)grvCart.FindControl("txt_productQuantity");
int currentQuantity = Int32.Parse(Regex.Replace(textQuantity.Text, #"[^\d]", ""));
try
{
conn.Open();
// Update the cart quantity if the id matches with the grid view data source
string query = string.Format("UPDATE tbl_cart SET product_quantity = '{0}' WHERE id = '{1}'", currentQuantity, btn.CommandArgument);
command.CommandText = query;
command.ExecuteNonQuery();
Response.Redirect("cart.aspx");
}
finally
{
conn.Close();
}
}
}
}
}

Try using the RowCommand event (especially since you already have the CommandArgument set up). That is the more appropriate way to handle this type of action (and that way you can just update one row at a time, without looping through all of them).
Handle the RowCommand event in your GridView declaration:
<asp:GridView ID="grv_cart" runat="server" AllowPaging="True"
AutoGenerateColumns="False" DataSourceID="sds_store" ShowHeader="True"
GridLines="None" CssClass="table" OnRowCommand="grv_cart_RowCommand">
And then your event handler would look like this:
protected void grv_cart_RowCommand(Object sender, GridViewCommandEventArgs e)
{
GridViewRow rowToUpdate = grv_cart.Rows[Int.Parse(e.CommandArgument)];
TextBox textQuantity = (TextBox)rowToUpdate.FindControl("txt_productQuantity");
int currentQuantity = Int32.Parse(Regex.Replace(textQuantity.Text, #"[^\d]", ""));
try
{
conn.Open();
// Update the cart quantity if the id matches with the grid view data source
string query = string.Format("UPDATE tbl_cart SET product_quantity = '{0}' WHERE id = '{1}'", currentQuantity, e.CommandArgument);
command.CommandText = query;
command.ExecuteNonQuery();
Response.Redirect("cart.aspx");
}
finally
{
conn.Close();
}
}
Note: You'll want to remove the OnClick handler from the update button:
<asp:Button ID="btn_update" Text="Update" runat="server"
CommandArgument='<%# Eval("id") %>' CssClass="btn btn-warning" />

Trying to access the label in ListView

I have a ListView control with DataPager, i am trying to show results from database into ListView the database have field in which i have store content from ajaxhtmlextender i have bind ListView with database like this
protected void ListEvents()
{
conn = new SqlConnection(connSting);
cmdListEvent = new SqlCommand("SELECT * FROM LatestEvents",conn);
table = new DataTable();
conn.Open();
adpter = new SqlDataAdapter(cmdListEvent);
adpter.Fill(table);
ListEvent.DataSource = table;
ListEvent.DataBind();
conn.Close();
}
and the .aspx file
<asp:ListView ID="ListEvent" runat="server"
OnItemDataBound="ListEvent_ItemDataBound" >
<LayoutTemplate>
<asp:PlaceHolder runat="server" ID="itemPlaceholder"></asp:PlaceHolder>
</LayoutTemplate>
<ItemTemplate>
<div class="contmainhead">
<h1 id="evhead"><asp:Label ID="LabelTittle" runat="server"><%#Eval("Tittle") %></asp:Label></h1>
</div>
<div class="contmain">
<asp:Label ID="LabelBody" runat="server"> <%#Eval("Body") %></asp:Label>
</div>
</ItemTemplate>
</asp:ListView>
It is giving the intended results but the problem is the label
<asp:Label ID="LabelBody" runat="server"> <%#Eval("Body") %></asp:Label>
showing all the formatted text and images as html markup, i know to work the label perfectly i have to use this function
Server.HtmlDecode();
i tried it like this
protected void ListEvent_ItemDataBound(object sender, ListViewItemEventArgs e)
{
if (e.Item.ItemType == ListViewItemType.DataItem)
{
Label LabelBody = (Label)e.Item.FindControl("LabelBody");
LabelBody.Text = Server.HtmlDecode(LabelBody.Text);
}
}
But the label shows nothing. . so how can i make the label show the content correctly?
Your help will be greatly appreciated . .Thanx

protected void ListEvent_ItemDataBound(object sender, ListViewItemEventArgs e)
{
if (e.Item.ItemType == ListViewItemType.DataItem)
{
ListViewDataItem dataItem = (ListViewDataItem) e.Item;
Label LabelBody = (Label)e.Item.FindControl("LabelBody");
LabelBody.Text = (string) DataBinder.Eval(dataItem.DataItem, "Body");
}
}
Please make sure there is a column named in your returned datatable
and also remove the <%# EVAL %> tag from the text attribute of your label, leave it empty or do not specify the attribute in your aspx

try
<asp:Label ID="LabelBody" runat="server" text='<%#Eval("Body") %>' />
EDIT :
if the above didn't work try :
<asp:Label ID="LabelBody" runat="server" text="<% #Eval("Body").ToString() %>" />

Binding RowCommand to fire when any cell in a row is clicked

My GridView basically displays a summarized version of data in the database.
What I want to do is set it up so that when you click anywhere in a row in the GridView, it should execute a set procedure that'll hide the panel that contains the GridView and display a panel that will show you the details of the item you clicked.
<asp:Panel runat="server" ID="pnlList">
<div class="rightalign">
<asp:Label runat="server" ID="lblCount"></asp:Label>
</div>
<asp:GridView runat="server" ID="gvItems" DataKeyNames="mailid"
AutoGenerateColumns="false" onrowdatabound="gvItems_RowDataBound"
Width="100%" OnSelectedIndexChanged="gvItems_SelectedIndexChanged">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:CheckBox runat="server" ID="chkSelect" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<ItemTemplate>
<asp:Label runat="server" ID="lblStatus" Text='<%# DataBinder.Eval(Container.DataItem, "status") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="firstname" HeaderText="From" SortExpression="firstname" />
<asp:BoundField DataField="datesent" HeaderText="Date" SortExpression="datesent" DataFormatString="{0:yyyy/MM/dd HH:mm}" />
<asp:BoundField DataField="subject" HeaderText="Subject" SortExpression="subject" />
</Columns>
</asp:GridView>
</asp:Panel>
<asp:Panel runat="server" ID="pnlMail">
<p>From: <asp:Label runat="server" ID="lblFrom"></asp:Label><br />
Sent On: <asp:Label runat="server" ID="lblDate"></asp:Label><br />
Subject: <asp:Label runat="server" ID="lblSubject"></asp:Label></p>
<p><asp:Label runat="server" ID="lblMessage"></asp:Label></p>
</asp:Panel>
I figured I'd use the SelectedIndexChanged event, but I'm not sure how to actually make it fire off clicks on the cells.
Here's the code I've got:
protected void gvItems_SelectedIndexChanged(object sender, EventArgs e)
{
int index = gvItems.SelectedIndex;
string mailid = gvItems.DataKeys[index].Value.ToString();
getMailDetail(mailid);
pnlMail.Visible = true;
}
protected void getMailDetail(string id)
{
int mailid = int.Parse(id);
MySqlContext db = new MySqlContext();
string sql = "select m.datesent, m.subject, m.message, u.firstname, u.lastname from mail m inner join users u on m.senderid = u.userid where m.mailid = #id";
List<MySqlParameter> args = new List<MySqlParameter>();
args.Add(new MySqlParameter() { ParameterName = "#id", MySqlDbType = MySqlDbType.Int32, Value = mailid });
MySqlDataReader dr = db.getReader(sql, args);
if (dr.HasRows)
{
dr.Read();
lblFrom.Text = (string)dr["firstname"] + " " + (string)dr["lastname"];
lblDate.Text = (string)dr["datesent"];
lblSubject.Text = (string)dr["subject"];
lblMessage.Text = (string)dr["message"];
}
dr.Close();
}
How can I make clicks on the cells in a row fire an event that'll do the work I need done?
Any help will be appreciated!

I can see two possible solutions here. First - handle click on the row on client side, send Ajax request to some HttpHandler that will return you necessary mail details, and display the returned info. Steps to achieve this:
Assign a client side handler too row click:
protected void gvItems_RowDataBound(object sender, GridViewRowEventArgs e)
{
if(e.Row.RowType == DataControlRowType.DataRow)
{
e.Row.Attributes["onClick"] = "showMailDetails(" + DataBinder.Eval(e.Row.DataItem, "id") + ")";
}
}
And define the client side function:
function showMailDetails(mailId) {
$.get(
url: 'url to HttpHandler here',
data: {id: mailId},
success: function(data) {
var pnlMail = $('#<%= pnlMail.ClientID %>');
// display data here
pnlMail.show()
});
}
Another way is to handle click on client side and then emulate RowCommand event by doing something like this:
protected void gvItems_RowDataBound(object sender, GridViewRowEventArgs e)
{
if(e.Row.RowType == DataControlRowType.DataRow)
{
e.Row.Attributes["onClick"] = ""javascript:__doPostBack('" + gvItems.ClientID + "','MailDetailsCommand$" + DataBinder.Eval(e.Row.DataItem, "id") + "')";
}
}
And then on server side go like you already did, just in RowComamnd handler:
protected void gvItems_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "MailDetailsCommand") {
// ...
}
}
Although I would not recommend this method - using _doPostBack manully is not considered as a best practice.

you give a template field which consist the button or a button field and then you can the give the commandname as something and then you can use the gridview commandeventargs and based on the commandname you can do whatever you want, and you can use the OnRowCommand to fire an event :D hope this will help you .....
You can even go for adding the onclick attribute to the cell in the RowDataBound Event, if there are any restrictions of not having the button field or like that