I have a webpart in a control that I am using on a webpage. The webpage uses a master page and there is a content holder in the MP that can hold controls for alignment/design issues. Everything works well with this but the webpart control. When i put the webpart in the container i lose the ability to move the webparts around but as soon as i move it out of the container it works fine.
default.aspx
/// <summary>
/// Set the selected item equal to the current display mode.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
public void Page_PreRender(object sender, EventArgs e)
{
MyWebPartManager wpm = (MyWebPartManager)WebPartManager.GetCurrentWebPartManager(Page);
Control control = (Control)Master.FindControl("divReturnBack");
if (control != null)
{
control.Visible = true;
control.Controls.Add(DisplayModeMenul1);
}
}
displaymode.ascx
MyWebPartManager webPartManager;
public void Page_Init(object sender, EventArgs e)
{
Page.InitComplete += new EventHandler(InitComplete);
}
public void InitComplete(object sender, System.EventArgs e)
{
webPartManager = (MyWebPartManager)WebPartManager.GetCurrentWebPartManager(Page);
String browseModeName = WebPartManager.BrowseDisplayMode.Name;
foreach (WebPartDisplayMode mode in
webPartManager.SupportedDisplayModes)
{
String modeName = mode.Name;
if (mode.IsEnabled(webPartManager))
{
ListItem listItem = new ListItem(modeName, modeName);
ddlDisplayMode.Items.Add(listItem);
}
}
}
public void ddlDisplayMode_SelectedIndexChanged(object sender, EventArgs e)
{
String selectedMode = ddlDisplayMode.SelectedValue;
WebPartDisplayMode mode = webPartManager.SupportedDisplayModes[selectedMode];
if (mode != null)
{
webPartManager.DisplayMode = mode;
}
}
public void Page_PreRender(object sender, EventArgs e)
{
ListItemCollection items = ddlDisplayMode.Items;
int selectedIndex = items.IndexOf(items.FindByText(webPartManager.DisplayMode.Name));
ddlDisplayMode.SelectedIndex = selectedIndex;
}
I moved this code outside the postback section and it works fine now.
// move to container in masterpage
Control control = (Control)Master.FindControl("divReturnBack");
if (control != null)
{
control.Visible = true;
control.Controls.Add(DisplayModeMenul1);
}
Related
I fill some controls with data from data base, by calling a select method
and I change the values to update it, but when I press update button, it takes the values that called at the page load, and ignore all changes.
how can I avoid this ?
thanks in advance : )
here is a simple code to present my problem
SelectBLL _selectbll;
string _title = string.Empty;
string _details = string.Empty;
#region Page Load
protected void Page_Load(object sender, EventArgs e)
{
GetUMedicineDetails();
}
#endregion
#region Get UMedicine Details
private void GetUMedicineDetails()
{
_selectbll = new SelectBLL();
_selectbll._GetUMedicineDetails(Request.QueryString[0].ToString(), ref _title, ref _details);
#region Bind Controls
txtdetails.Text = _details;
txttitle.Text = _title;
#endregion
}
#endregion
#region Update Button
protected void btnupdate_Click(object sender, EventArgs e)
{
_UpdateUMedicine();
}
#endregion
#region UpdateU Medicine
public void _UpdateUMedicine()
{
_updatebll = new UpdateBLL();
_updatebll._UpdateUMedicine(
Convert.ToInt32(Request.QueryString[0]), txtdetails.Text, txttitle.Text);
}
#endregion
Page.IsPostBack Property: Gets a value that indicates whether the page is being rendered for the first time or is being loaded in response to a postback.
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
GetUMedicineDetails();
}
}
Also, Refer:
How to: Determine How ASP.NET Web Pages Were Invoked
DataBind only if !Page.IsPostaBack:
protected void Page_Load(object sender, EventArgs e)
{
if(!Page.IsPostaBack)
GetUMedicineDetails();
}
I created a global.asax file for an asp.net application. I run some code in the session_start method. The code does not get executed. Is there some type of procedure for using a global.asax file in asp.net 2.0?
I have the asax file itself and also a codebehind file.
Thank you!
Edit:
asax file:
<%# Application Codebehind="Global.asax.cs" Inherits="GrowUp.Global" %>
The code behind file:
using System;
using System.Collections;
using System.ComponentModel;
using System.Web;
using System.Web.SessionState;
namespace Ligdol
{
/// <summary>
/// Summary description for Global.
/// </summary>
public class Global : System.Web.HttpApplication
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
public Global()
{
InitializeComponent();
}
protected void Application_Start(Object sender, EventArgs e)
{
Application["HostName"] = System.Configuration.ConfigurationSettings.AppSettings["HostName"];
Application["counter"] = 1;
}
protected void Session_Start(Object sender, EventArgs e)
{
// Get the count from the application variable
int counter = int.Parse(Application["counter"].ToString());
//Check if a cookie exists.
if(HttpContext.Current.Request.Cookies["ligdolVersion"] != null)
{
//If a cookie exists, we need to redirect the user to the respective site.
if(HttpContext.Current.Request.Cookies["ligdolVersion"].ToString() == "new")
{
Response.StatusCode = 302;
Response.Status = "Moved temporarily";
Response.Redirect("http://beta.ligdol.co.il");
return;
}
else if(HttpContext.Current.Request.Cookies["ligdolVersion"].ToString() == "old")
{
return;
}
}
else if (counter == 40)
{
// If a cookie does not already exist,
//we need to check if the user is to be allowed to continue to the old site
//or be redirected to the new site.
//Note in a file that a user was redirected, so we can get an estimate of how many are being redirected.
System.IO.TextWriter tw = new System.IO.StreamWriter(#"redirect.log");
tw.WriteLine("Redirected to new site.");
tw.Close();
// Reset counter.
Application["counter"] = 1;
//write cookie made to expire in 30 days, by then the experiment will be over (we hope!).
HttpCookie cookie = new HttpCookie("ligdolVersion");
DateTime dtNow = DateTime.Now;
TimeSpan tsSpan = new TimeSpan(30, 0, 0, 0, 0);
cookie.Expires = dtNow + tsSpan;
cookie.Value = "new";
Response.Cookies.Add(cookie);
Response.Redirect("http://beta.ligdol.co.il");
return;
}
else
{
System.IO.TextWriter tw = new System.IO.StreamWriter(#"redirect.log");
tw.WriteLine("Redirected to old site.");
tw.Close();
HttpCookie cookie = new HttpCookie("ligdolVersion");
DateTime dtNow = DateTime.Now;
TimeSpan tsSpan = new TimeSpan(30, 0, 0, 0, 0);
cookie.Expires = dtNow + tsSpan;
cookie.Value = "old";
Response.Cookies.Add(cookie);
return;
}
}
protected void Application_BeginRequest(Object sender, EventArgs e)
{
}
protected void Application_EndRequest(Object sender, EventArgs e)
{
}
protected void Application_AuthenticateRequest(Object sender, EventArgs e)
{
}
protected void Application_Error(Object sender, EventArgs e)
{
}
protected void Session_End(Object sender, EventArgs e)
{
}
protected void Application_End(Object sender, EventArgs e)
{
}
#region Web Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
}
#endregion
}
}
The issue was the codebehind file. Once I put the code inline inside the asax file, it worked. This might be the only solution for old website projects.
I want to preserve the dynamically created control when postback occurs .
protected void Page_Load(object sender, EventArgs e)
{
}
private void CreateTable()
{
HtmlTableRow objHtmlTblRow = new HtmlTableRow();
HtmlTableCell objHtmlTableCell = new HtmlTableCell();
objHtmlTableCell.Controls.Add(new TextBox());
objHtmlTblRow.Cells.Add(objHtmlTableCell);
mytable.Rows.Add(objHtmlTblRow);
this.SaveControlState();
// this.Controls.Add(mytable);
}
protected void Button1_Click(object sender, EventArgs e)
{
CreateTable();
}
It can be achieved by calling CreateTable() in Page_Load. Is there any alternative way to preserve the control
Thanks
You can add them to a List when you create them and save your List to Session. On postback (Page_Load) load them from your Session to your Page.
the below code should work
protected void Page_PreInit(object sender, EventArgs e)
{
Control myControl = GetPostBackControl(this.Page);
}
protected override void OnInit(EventArgs e)
{
base.OnInit(e);
CreateTable()
}
public static Control GetPostBackControl(Page thisPage)
{
Control ctrlPostedback = null;
string ctrlName = thisPage.Request.Params.Get("__EVENTTARGET");
if (!String.IsNullOrEmpty(ctrlName))
{
ctrlPostedback = thisPage.FindControl(ctrlName);
}
else
{
foreach (string Item in thisPage.Request.Form)
{
Control c = thisPage.FindControl(Item);
if (((c) is System.Web.UI.WebControls.Button))
{
ctrlPostedback = c;
}
}
}
return ctrlPostedback;
}
The code works from UpdatePanel
Reference:http://www.asp.net/ajax/videos/how-to-dynamically-add-controls-to-a-web-page
I Add Control Dynamiclly but; easc Postback event my controls are gone. I Can not see again my controls.
So How can I add control ?
Because you must recreate your controls on every postback,
see this article
Add the controls in the Page's Init event and they will be preserved in viewstate when posting back. Make sure they have a unique ID.
See this link...
ASP.NET Add Control on postback
A very trivial example..
public partial class MyPage : Page
{
TextBox tb;
protected override void OnInit(EventArgs e)
{
base.OnInit(e);
tb = new TextBox();
tb.ID = "testtb";
Page.Form.Controls.Add(tb);
}
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
//tb.Text will have whatever text the user entered upon postback
}
}
You should always assign a unique ID to the UserControl in its ID property after control is loaded. And you should always recreate UserControl on postback.
To preserve posback data (i.e. TextBox'es) you must load UserControl in overriden LoadViewState method after calling base.LoadViewState - before postback data are handled.
Add controls in runtime and save on postback:
int NumberOfControls = 0;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
ViewState["b1"] = 0;
}
else
{
if ((int)ViewState["b1"] > 0)
{
CreateBtn();
}
}
}
protected void btn1_Click(object sender, EventArgs e)
{
NumberOfControls = (int)ViewState["b1"];
Button b1 = new Button();
// b1.Attributes.Add("onclick", "x()");
b1.Text = "test2";
b1.ID = "b1_" + ++NumberOfControls;
b1.Click +=new System.EventHandler(btn11);
Panel1.Controls.Add(b1);
ViewState["b1"] = NumberOfControls;
}
protected void CreateBtn()
{
for (int i = 0; i < (int)ViewState["b1"];i++)
{
Button b1 = new Button();
// b1.Attributes.Add("onclick", "x()");
b1.Text = "test2";
b1.ID = "b1_" + i;
b1.Click += new System.EventHandler(btn11);
Panel1.Controls.Add(b1);
}
}
protected void btn11(object sender, System.EventArgs e)
{
Response.Redirect("AboutUs.aspx");
}
I have a datagrid (Asp.Net) with dynamically generated checkbox column..I am not able to generate the checkedChanged event for the checkbox..
Here is my code:
public class ItemTemplate : ITemplate
{
//Instantiates the checkbox
void ITemplate.InstantiateIn(Control container)
{
CheckBox box = new CheckBox();
box.CheckedChanged += new EventHandler(this.OnCheckChanged);
box.AutoPostBack = true;
box.EnableViewState = true;
box.Text = text;
box.ID = id;
container.Controls.Add(box);
}
public event EventHandler CheckedChanged;
private void OnCheckChanged(object sender, EventArgs e)
{
if (CheckedChanged != null)
{
CheckedChanged(sender, e);
}
}
}
and Here is the event
private void OnCheckChanged(object sender, EventArgs e)
{
}
Thanks In advance
When do you add your custom column? If it is on load, then it is too late. Load it on init. I.e. following works with your code:
protected void Page_Init(object sender, EventArgs e)
{
ItemTemplate myTemplate = new ItemTemplate();
myTemplate.CheckedChanged += new EventHandler(myTemplate_CheckedChanged);
TemplateField col = new TemplateField();
col.ItemTemplate = myTemplate;
col.ItemStyle.Wrap = false;
grid.Columns.Add(col);
}
If your checkbox ID's are not being set the same way on every postback, then they can never be connected to the event handlers when it comes time to process the events. Where is your field "id" coming from?