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Avoid controls with same ID

I'm creating dynamically controls, assigning it at the same dynamically names and ID's but when I click over a button "A" and then over the button "B" and then again to the button "A" this throw me an error
Multiple controls with the same ID were found. FindControl requires that controls have unique IDs.
this is my code and how I try to avoid the repeating I
protected void DynamicButton()
{
//BAD TOOLS INTO THE LIST AND SHOW
List.ListUsers listsArea = new List.ListUsers();
List<Data.Area> Area = listsArea.AreaList();
List<Data.Area> ListOfEquiposNoOk = Area.Where(x => x.AREA == "ENG" && x.STANDBY == 1).ToList();
List<Button> BotonesBad = new List<Button>();
var TeamBad = ListOfEquiposNoOk.Select(x => x.TEAM).Distinct().ToList();
foreach (var team in TeamBad)
{
Button newButtonBad = new Button();
if (newButtonBad.ID != newButtonBad.ID)
{
BotonesBad = Bad.Controls.OfType<Button>().ToList();
BotonesBad.Add(newButtonBad);
}
else
{
newButtonBad.CommandName = "Btn" + Convert.ToString(team);
newButtonBad.ID = "BtnB_" + Convert.ToString(team);
newButtonBad.Text = team;
newButtonBad.CommandArgument = "ENG";
newButtonBad.Click += new EventHandler(newButton_Click);
Bad.Controls.Add(newButtonBad);
newButtonBad.Click += new EventHandler(newButton_Click);
newButtonBad.CssClass = "btn-primary outline separate";
}
}
I need the ID's to fire an UpdatePanel
ADDED
public partial class Dashboard : System.Web.UI.Page
{
static bool enableGood = false;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
DynamicButton();
}
else if(enableGood)
{
DynamicButton();
}
}
protected void DButton(object sender, EventArgs e)
{
ScriptManager.RegisterStartupScript(this, this.GetType(), "Pop", "showAndHide();", true);
enableGood = true;
DynamicButton();
}

Assuming "team" is an object in this line:
newButtonBad.ID = "BtnB_" + Convert.ToString(team);
There could be your problem. ".ToString()" usually returns the type as string. So every button will get the same name (since they are all of type "team").
You could override ToString() in your team object, or use a specific team property (e.g team.ID). You could use the property like this:
newButtonBad.ID = "BtnB_" + team.ID.ToString();
Also as already pointed out in the comments, change your evaluation from
if (newButtonBad.ID != newButtonBad.ID)
to
if (team.ID != newButtonBad.ID)
That should do the trick.

looping through table to hide button in repeater

I have a dataset full of records, I want for all those that exist in this dataset, to hide my LinkButton in the ASP.NET Repeater, what am I doing wrong here?
C#:
protected void Page_PreRender(object sender, EventArgs e)
{
var getOperator = _administrationSystem.GetOperatorsInformation(userId); //Dataset
if (rptAdd.Items.Count > 0) //rptAdd is a Repeater
{
for (var count = 0; count < rptAdd.Items.Count; count++)
{
var btnSubmit = (LinkButton)rptAdd.Items[count].FindControl("btnSubmitOperator");
foreach (var attendants in getOperator.Tables[0].Rows)
{
btnSubmit.Visible = attendants != null;
}
}
}
}

i want for all those that exists in this dataset, to hide my linkbutton
btnSubmit.Visible = attendants != null;
if attendant is not null (attendant exists), set btnSubmit to visible
But your post sounds more like you want to hide the button if an attendant exists:
btnSubmit.Visible = attendants == null;

Retrieve value from dynamic dropdownlist in placeholder C#

I have dynamic drop down lists that are created based on what's selected in the list box.. When clicking confirm this is when the drop down lists are created. Clicking save is where I attempt to retrieve the values. However I am unable to retrieve that values that are in the drop down lists.
Code:
protected void btnConfirm_Click(object sender, EventArgs e)
{
int ID = 0;
foreach (string value in values)
{
MyStaticValues.alEdit.Add(value);
CreateEditForm(value, ID);
ID += 1;
}
if (values.count != 0)
{
btnSave.Visible = true;
btnConfirm.Enabled = false;
}
}//End of btnConfirm_Click
protected void CreateEditForm(string Value, int ID)
{//Creates an edit form for the value inserted.
string name = value;
//This part adds a header
phEditInventory.Controls.Add(new LiteralControl("<h2>" + name + "</h2>"));
phEditInventory.Controls.Add(new LiteralControl("<div class=\"clearfix\"></div>"));
//Create a label
Label lblName = new Label();
lblName.Text = "Name";
lblName.ID = "lblName" + ID;
lblName.CssClass = "control-label";
//Create a Drop Down List
DropDownList ddlName = new DropDownList();
ddlName.ID = "ddlName" + ID;
ddlName.CssClass = "form-control";
//Set default N/A Values For Drop Down List
ddlName.Items.Add(new ListItem("N/A", Convert.ToString("0")));
//The Rest of the Values are populated with the database
//Adds the controls to the placeholder
phEditInventory.Controls.Add(lblName);
phEditInventory.Controls.Add(ddlName);
phEditInventory.Controls.Add(new LiteralControl("<div class=\"clearfix\"></div>"));
} //End of CreateEditForm
protected void btnSave_Click(object sender, EventArgs e)
{
string name = "";
try
{
for (int i = 0; i < MyStaticValues.alEdit.Count; i++)
{
string nameID = "ddlName" + i.ToString();
DropDownList ddlName = (DropDownList)phEditInventory.FindControl(nameID);
name = ddlName.SelectedValue.ToString();
}
}
catch (Exception ex)
{
}
phEditInventory.Visible = false;
btnSave.Visible = false;
MyStaticValues.alEdit.Clear();
}//End of btnSave_Click Function

Your problem is that the dynamically created dropdown lists are not maintained on postback. When you click the Save button, a postback occurs, and the page is re-rendered without the dynamically created dropdowns. This link may help.
Maintain the state of dynamically added user control on postback?

Accessing dynamically generated dropdownlist in Gridview_RowUpdating event

I am using Gridview with AutoGenerateColumns="True", so gridview columns are generated dynamically. Now in case of edit, I am adding dropdownlist dynamically for one of the field in the gridview. Please see following code:
protected void grdViewConfig_RowEditing(object sender, GridViewEditEventArgs e)
{
grdViewConfig.EditIndex = e.NewEditIndex;
BindGridView();
clientBAL = new TMIWsBALClient();
var lstAppIds = clientBAL.GetDistinctApplicationIds();
GridViewRow grdRow = grdViewConfig.Rows[e.NewEditIndex];
for (int i = 0; i < grdRow.Cells.Count; i++)
{
if (grdRow.Cells[i].GetType().Equals(typeof(DataControlFieldCell)))
{
DataControlFieldCell dcField = (DataControlFieldCell )grdRow.Cells[i];
if (dcField.ContainingField.HeaderText.ToLower().Equals("applicationid"))
{
DropDownList drpDwnAppIds = new DropDownList();
drpDwnAppIds.ID = "drpDwnAppIds";
drpDwnAppIds.DataSource = lstAppIds;
drpDwnAppIds.DataBind();
var tb = dcField.GetAllControlsOfType<TextBox>(); ;// grdRow.Cells[i].GetAllControlsOfType<TextBox>();
TextBox firstTb = (TextBox)tb.First();
foreach (ListItem lstItem in drpDwnAppIds.Items)
{
if (firstTb.Text.Equals(lstItem.Text, StringComparison.CurrentCultureIgnoreCase))
{
lstItem.Selected = true;
}
}
dcField.Controls.Remove(firstTb);
dcField.Controls.Add(drpDwnAppIds);
}
}
}
}
Now in Gridview_RowUpdating event, I am trying to fetch the dropdownlist in similar way, but I am unable to get it. GetAllControlsOfType() is an extension method, which will return all the child controls under selected parent. In this case, parent is gridview cell and child control is dropdownlist. But it is returning null.
protected void grdViewConfig_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
strTableName = txtTable.Text.Trim();
string strAppId;
GridViewRow grdRow = grdViewConfig.Rows[grdViewConfig.EditIndex];
for (int i = 0; i < grdRow.Cells.Count; i++)
{
if (grdRow.Cells[i].GetType().Equals(typeof(DataControlFieldCell)))
{
DataControlFieldCell dcField = (DataControlFieldCell)grdRow.Cells[i];
if (dcField.ContainingField.HeaderText.ToLower().Equals("applicationid"))
{
var drpDwn = dcField.GetAllControlsOfType<DropDownList>();
DropDownList drpDwnAppIds = (DropDownList)drpDwn.First();
strAppId = drpDwnAppIds.SelectedValue;
}
}
}
}
What am I missing? Please help. Also let me know if more information is needed.
Thank you in advance.

Dynamically generated controls need to be recreated on every postback. In your case the DropDownList controls you created no longer exist when you hit the grdViewConfig_RowUpdating handler.
Generally in this sort of case you would set AutoGenerateColumns to false and manually define your columns which would allow you to define a TemplateField which contains an ItemTemplate for read only mode and an EditItemTemplate for edit mode which could then contain your DropDownList.

Multiview has Views added programmatically disappear when trying to change view

I have this code which adds a x number of views to a Multiview control. The Multiview control exist on the page with only one view. on page init I create x number of views with a GridView control added to each of these views when I come to loop through to find which one I want to show the Multiview control says it has only 1 view.
protected void variantRepeat_ItemCommand(object source, RepeaterCommandEventArgs e)
{
if (e.CommandSource.GetType() == typeof(LinkButton))
{
string theID = ((LinkButton)e.CommandSource).CommandArgument.ToString();
ViewCollection views = prodView.Views; //this has only 1 view the one that has been added on the source view of the .aspx page
foreach (View toDisplay in views)
{
if (toDisplay.ID == theID)
prodView.SetActiveView(toDisplay);
}
}
}
The code above loops to find the view and display it. Why do all the views disappear, I've stepped through and at init and after it has finished processing database queries it has x number of views > the 1 in source view.
Why does this control "lose" the views?
Init code:
protected void Page_Load(object sender, EventArgs e)
{
if (Request.QueryString == null || Request.QueryString.Count < 1)
Response.Redirect(Server.MapPath("~/Packages/"));
if (!Page.IsPostBack)
{
if (Request.QueryString["id"].ToString() == string.Empty)
Response.Redirect(Server.MapPath("~/Packages/"));
var id = Server.HtmlEncode(Request.QueryString["id"].ToString());
Guid packID = Guid.Parse(id);
using (var context = new GaleEntities())
{
var thePackage = context.PackageEnts.First(p => p.packageID == packID);
var theVariants = thePackage.Variants;
var mydatasource = new List<PackageEnt> { thePackage };
var myVariantDataSource = new List<Variant>();
foreach (Variant single in theVariants)
{
myVariantDataSource.Add(single);
}
packageForm.DataSource = mydatasource;
variantRepeat.DataSource = myVariantDataSource;
RenderProductGridviews(theVariants);
prodView.SetActiveView(prodView.Views[0]);
}
packageForm.DataBind();
variantRepeat.DataBind();
Page.DataBind();
}
}
protected void RenderProductGridviews(System.Data.Objects.DataClasses.EntityCollection<Variant> variantCol)
{
foreach (Variant packVar in variantCol)
{
View newView = new View();
GridView prodGrid = new GridView();
var myProdDataSource = new List<vw_VariantProduct>();
using (var context = new GaleEntities())
{
var singleProd1 = context.vw_VariantProduct.Where(vp => vp.variantID == packVar.variantID);
foreach (vw_VariantProduct extProd in singleProd1)
{
myProdDataSource.Add(extProd);
}
}
prodGrid.DataSource = myProdDataSource;
BoundField _column = new BoundField();
_column.DataField = "product_title";
_column.HeaderText = "Product";
prodGrid.Columns.Add(_column);
_column = new BoundField();
_column.DataField = "product_title";
_column.HeaderText = "Product";
prodGrid.Columns.Add(_column);
_column = new BoundField();
_column.DataField = "product_desc";
_column.HeaderText = "Description";
prodGrid.Columns.Add(_column);
_column = new BoundField();
_column.DataField = "product_time";
_column.HeaderText = "Time (mins)";
prodGrid.Columns.Add(_column);
_column = new BoundField();
_column.DataField = "quantity";
_column.HeaderText = "Quantity";
prodGrid.Columns.Add(_column);
prodGrid.DataBind();
newView.ID = packVar.variantID.ToString();
newView.Controls.Add(prodGrid);
prodView.Views.Add(newView);
}
}

Now, as usual almost all questions with the dynamic controls in ASP.Net words share the same common problem...
You need to create the dynamic controls on every post, you are only creating them the first time the page is loaded. Follow this simple rules:
Dynamic controls should be created in the PreInit event when you are not working with a master page, if you are, then create the controls in the Init event
Avoid setting properties that can be changed in each post in these events because when the view state is applied (in a post event) the properties will be overridden
Dynamic controls must be created every time the page is posted, avoid this if(!this.IsPostBack) this.CreatemyDynamicControls();
When you create the controls in the PreInit or Init events, their states will be automatically set in a post event, which means in the LoadComplete event your controls will contain their state back even when you create them again in each post and even when you did not explicitly set their state. Note this behavior is different when you are dealing with controls created at design time, in that case, the event where the state has been set is the Load event
Event subscription should occur before the PageLoadComplete or they will not be raised
I have posted several answers about dynamic controls:
https://stackoverflow.com/a/11127064/1268570
https://stackoverflow.com/a/11167765/1268570
Click events on Array of buttons
Button array disappears after click event
Dynamically create an ImageButton
This piece of code creates dynamic controls on-demand, and each control keeps its state on each post
public partial class DynamicControlsOnDemand : System.Web.UI.Page
{
public int NumberOfControls
{
get
{
if (this.ViewState["d"] == null)
{
return 0;
}
return int.Parse(this.ViewState["d"].ToString());
}
set
{
this.ViewState["d"] = value;
}
}
protected void Page_PreLoad(object sender, EventArgs e)
{
this.CreateDynamicControls();
}
protected void addControl_Click(object sender, EventArgs e)
{
this.NumberOfControls = this.NumberOfControls + 1;
this.myPanel.Controls.Add(this.CreateTextbox(this.NumberOfControls));
}
private void CreateDynamicControls()
{
for (int i = 0; i < this.NumberOfControls; i++)
{
var t = this.CreateTextbox(i + 1);
t.TextChanged += (x, y) => this.lblMessage.Text += "<br/>" + (x as TextBox).ID + " " + (x as TextBox).Text;
this.myPanel.Controls.Add(t);
}
}
private TextBox CreateTextbox(int index)
{
var t = new TextBox { ID = "myTextbox" + index.ToString(), Text = "de" };
return t;
}
}
ASPX
<asp:Panel runat="server" ID="myPanel">
</asp:Panel>
<asp:Button Text="Add Control" runat="server" ID="addControl" OnClick="addControl_Click" />
<asp:Label ID="lblMessage" runat="server" />
Output

You first code block where you are setting the active View is based on an ItemCommand event, so I'm assuming this fires during a PostBack?
Your code which adds the additional views within Page_Load is only running if not a post back. Try removing the conditional if(!Page.IsPostBack) statement. You need to add dynamic controls on every page lifecycle.