public partial class Default2 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
GenerateButtons generate = new GenerateButtons();
generate.Generate5Controls(PlaceHolder1);
}
}
class GenerateButtons
{
PlaceHolder placeHolder;
public void Generate5Controls(PlaceHolder placeH)
{
placeHolder = placeH;
for (int i = 0; i < 5; i++)
{
Button newBtn = new Button();
newBtn.Click += btn_Click;
newBtn.Text = "PageLoadButton Created. Number: "+i;
placeHolder.Controls.Add(newBtn);
}
}
public void btn_Click(object sender, EventArgs e)
{
Button newBTN = new Button();
newBTN.Text = "A New Button was added by the button event btn_click";
newBTN.Click += btn2_Click;
placeHolder.Controls.Add(newBTN);
}
public void btn2_Click(object sender, EventArgs e)
{
Button newBTN = new Button();
newBTN.Text = "A New Button was added by the button event btn2_click";
placeHolder.Controls.Add(newBTN);
}
}
I want the events btn_click & btn2_click to fire every post back.. When i click the button that was programmatically created it disappears after each postback and its event doesnt fire (btn2_click). I know i could generate the button at the postback.. But I dont want to do that!! I want to know how I could update the state of the placeholder... so that the only button will appear and the 5 buttons generated in Generate5Controls(PlaceHolder placeH) to disappear.
I could use a bool Viewstate to prevent this generate.Generate5Controls(PlaceHolder1); from being execute..
But the question is how do I make the programmatically generated button to appear!?
You should generate controls on every PostBack or you can generate controls once, save in session and add generated controls from session on page_load event.
protected void Page_Load(object sender, EventArgs e)
{
if(Session["GeneratedButtons"] == null)
{
GenerateButtons generate = new GenerateButtons();
generate.Generate5Controls(PlaceHolder1);
}
else
{
List<Control> generatedControls = Session["GeneratedButtons"] as List<Control>;
foreach(Control oneControl in generatedControls)
{
PlaceHolder1.Controls.Add(oneControl);
}
}
}
class GenerateButtons
{
PlaceHolder placeHolder;
public void Generate5Controls(PlaceHolder placeH)
{
placeHolder = placeH;
List<Control> generatedControls = new List<Control>();
for (int i = 0; i < 5; i++)
{
Button newBtn = new Button();
newBtn.Click += btn_Click;
newBtn.Text = "PageLoadButton Created. Number: "+i;
placeHolder.Controls.Add(newBtn);
AddControlToSession(newBtn);
}
}
public void btn_Click(object sender, EventArgs e)
{
Button newBTN = new Button();
newBTN.Text = "A New Button was added by the button event btn_click";
newBTN.Click += btn2_Click;
placeHolder.Controls.Add(newBTN);
AddControlToSession(newBtn);
}
public void btn2_Click(object sender, EventArgs e)
{
Button newBTN = new Button();
newBTN.Text = "A New Button was added by the button event btn2_click";
placeHolder.Controls.Add(newBTN);
AddControlToSession(newBtn);
}
private void AddControlToSession(Control ctrl)
{
List<Control> generatedControls = Session["GeneratedButtons"] as List<Control>;
if(generatedControls == null)
{
generatedControls = new List<Control>();
}
generatedControls.Add(ctrl);
Session["GeneratedButtons"] = generatedControls;
}
}
Related
I'm creating dynamically buttons into a repeater like somebody recommend in previous questions I make into a Page_Init and I make some conditions but the problem persist, the button don't fire the assigned event
this is the first condition
public bool AssignClicked
{
get
{
return Convert.ToBoolean(ViewState["AssignClicked"]);
}
set
{
ViewState["AssignClicked"] = value;
}
}
then this is the code when I make click in the button that create the buttons changing into true the condition:
protected void DButton(object sender, EventArgs e)
{
AssignClicked = true;
Page_Init(sender, e);
Page_Load(sender, e);
}
And start the creations of the buttons
protected void Page_Init(object sender, EventArgs e)
{
if (AssignClicked)
{
ScriptManager.RegisterStartupScript(this, this.GetType(), "Pop", "showAndHide();", true);
Button Btn_clic = (Button)sender;
var name = Btn_clic.Text;
List.ListUsers listArea = new List.ListUsers();
List<Data.Area> Area = listArea.AreaList();
List<Data.Area> ListOfEquiposOk = Area.Where(x => x.AREA == name && x.STANDBY == 0).ToList();
var TeamFCH = ListOfEquiposOk.Select(x => x.TEAM).Distinct().ToList();
foreach (var team in TeamFCH)
{
Button newButton = new Button();
newButton.CommandName = "Btn" + Convert.ToString(team);
newButton.ID = "Btn_" + Convert.ToString(team);
newButton.Text = team;
newButton.CommandArgument = name;
newButton.Click += new EventHandler(newButton_Click);
Repeater1.Controls.Add(newButton);
newButton.CssClass = "btn-primary outline separate";
}
}
}
but when I click over the button created this doesn't do anything
I want to create a form programmatically, then add controls to that for and handle click events on those controls,
such as click on button should show impact on text box
namespace formwizard
{
public partial class Form1 : Form
{
Form form = new Form();
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
form.Text = formtitle.Text;
int count = Convert.ToInt32(FormName.Text);
int i=1;
while (i<= count)
{
TextBox tb = new TextBox();
tb.Text = "Text box"+ i.ToString();
Button bt = new Button();
bt.Text = "Button" + i.ToString();
tb.Location = new Point(15, i*20);
bt.Location = new Point(120, i*20);
bt.Name = "Button" + i.ToString();
form.Controls.Add(tb);
form.Controls.Add(bt);
bt.Click +=new EventHandler(bt_Click);
i++;
}
// form.Controls.Add(...);
form.ShowDialog();
}
void bt_Click(object sender, EventArgs e)
{
Button btn = (Button) sender;
string a=btn.Text.Substring(6,btn.Text.Length-6);
MessageBox.Show("You clicked Button "+a);
}
}
}
Your code is correct, the only problem I see is you haven't initialized a new instance of Form:
Form form2 = new Form();
//now add your controls to this form
//show form using "form2.ShowDialog()"
I want to add buttons to my page dynamically. It will depend on the number of results from a SELECT statement. I
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
for (int i = 0; i < Query.length; i++)
{
Button btn = new Button();
btn.ID = "Button" + i;
btn.Click += new EventHandler(btn_Click());
btn.Text = i.ToString();
pagingPanel.Controls.Add(btn);
}
}
}
But I want each button to have it's own custom event handler. If I click one button, I want it do have a different result than if I click another. I would like to do something like this where I can pass an aditional parameter:
protected void btn_Click(object sender, EventArgs e, string test)
{
System.Diagnostics.Debug.WriteLine(test);
}
Perhaps I don't know which objects to pass? Or maybe I am approaching this the wrong way.
How do I achieve the desired results?
Try this:
protected void Page_Load(object sender, EventArgs e)
{
// you do not use !IsPostBack here
//count of func must be equal with 'Query.Length'
string[,] arr ={
{"func1","hello world"},
{"func2","Hello ASP.NET"}
};
for (int i = 0; i < Query.Length; i++)//I assume length is 2
{
Button btn = new Button();
btn.ID = arr[i, 0];
btn.CommandArgument = arr[i, 1];
btn.Click += new EventHandler(btn_Click);
btn.Text = i.ToString();
pagingPanel.Controls.Add(btn);
}
}
protected void btn_Click(object sender, EventArgs e)
{
Button btn = (Button)sender;
System.Reflection.MethodInfo methodInfo = typeof(_Default2).GetMethod(btn.ID); //_Default2 is class name of code behind
if (methodInfo != null)
{
object[] parameters = new object[] { btn.CommandArgument};
methodInfo.Invoke(this,parameters);
}
}
public void func1(object args)
{
string test = args.ToString();
Response.Write(test);
}
public void func2(object args)
{
string test = args.ToString();
Response.Write(test);
}
First and foremost - you have to create buttons whether it is postback or not. The button click is the reason for the postback, if you don't have buttons - what will be clicking?
Second, add to your page class:
Dictionary<Button, ButtonInfo> fButtonLookup = new Dictionary<Button, ButtonInfo>();
Then, where you create buttons:
fButtonLookup.Clear();
for (int i = 0; i < Query.length; i++)
{
Button btn = new Button();
fButtonLookup.Add(btn, new ButtonInfo() { whatever information about this button you want to keep});
...
}
Then, in your button click:
protected void btn_Click(object sender, EventArgs e)
{
Button btn = (Button)sender;
if (fButtonLookup.ContainsKey(btn))
{
ButtonInfo info = fButtonLookup[btn];
// do waht you need with button information
}
}
You could just check sender to see which button was clicked:
protected void btn_Click(object sender, EventArgs e)
{
if (sender == btnOne)
performBtnOne("foo");
else if (sender == btnTwo)
performButtonTwo("bar");
}
To expand on itsme86...
protected void btn_Click(object sender, EventArgs e)
{
Button btn = (Button)sender; //Now you have an instantiated version of the button pressed.
switch (btn.Name)
{
case "foo":
performBtnOne();
break;
case "bar":
performBtnTwo();
break;
default:
performUnexpectedButton();
break;
}
}
I have a Form on which there are two controls, a Button and a TextBox.
These controls are created at runtime.
When I click the Button, I want to do some operations with the TextBox.Text property.
But, with this code I can't:
private void Form1_Load(object sender, EventArgs e)
{
TextBox txb = new TextBox();
this.Controls.Add(txb);
Button btn = new Button();
this.Controls.Add(btn);
btn.Click += new EventHandler(btn_Click);
}
Here I'm trying to find it:
public void btn_Click(object sender, EventArgs e)
{
foreach (var item in this.Controls)
{
if (item is TextBox)
{
if (((TextBox)item).Name=="txb")
{
MessageBox.Show("xxx");
}
}
}
}
You don't have a Textbox with Name "txb". so, this expression will always be false: if(((TextBox)item).Name=="txb")
try this codes:
private void Form1_Load(object sender, EventArgs e)
{
TextBox txb = new TextBox();
txb.Name = "txb";
this.Controls.Add(txb);
Button btn = new Button();
this.Controls.Add(btn);
btn.Click += new EventHandler(btn_Click);
}
I would save off a reference to your TextBox.
TextBox txb;
private void Form1_Load(object sender, EventArgs e)
{
txb = new TextBox();
this.Controls.Add(txb);
Button btn = new Button();
this.Controls.Add(btn);
btn.Click += new EventHandler(btn_Click);
}
the dynamic controls went missing right after i click it, why is this happening, and how do i fix it.
protected void Page_Load(object sender, EventArgs e)
{
/*DropDownList1_SelectedIndexChanged(sender, e);
Label1.Text += "<br/>huh?";
Label1.Text = MapPath("dawd");*/
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
//PlaceHolder1.Controls.Clear();
for (int i = 0; i < DropDownList1.SelectedIndex + 1; i++)
{
CheckBox cb = new CheckBox();
cb.AutoPostBack = true;
cb.CheckedChanged += new EventHandler(cb_CheckedChanged);
PlaceHolder1.Controls.Add(cb);
PlaceHolder1.Controls.Add(new LiteralControl("<br/>"));
}
}
void cb_CheckedChanged(object sender, EventArgs e)
{
//DropDownList1_SelectedIndexChanged(sender, e);
Label1.Text += "<br/>adsd";
//throw new NotImplementedException();
}
cheers, Jaf
Dynamically created controls have to be recreated in every postback, or they will not be available and non of their events will fire.
You are only ever adding the checkboxes when the dropdownlist changes, so any other postback will not add them.
It is best to create your dynamic controls on the page OnInit event.
Read about the page life cycle here.
Create a panel
Do not create on page_load
Add this code
protected override void CreateChildControls()
{
base.CreateChildControls();
loadCheckbox();
}
public void loadCheckbox()
{
int checkCount = 10;
CheckBox[] chk = new CheckBox[checkCount];
for(int i == 0; i<=10; i++)
{
chk[i] = new CheckBox();
chk[i].ID = rCmt.cmtkey;
chk[i].Text = rCmt.rootcommitteename;
Panel1.Controls.Add(chk[i]);
}
}