UserControl: How to set Output Cache duration programmatically? - asp.net

UserControl: How to set Output Cache duration programmatically?

Make a public property on the UserControl which you could use to change the duration of the cache.
public Double CacheDuration { get; set; }
protected void Page_Load(object sender, EventArgs e)
{
Response.Cache.SetCacheability(HttpCacheability.Server);
Response.Cache.SetExpires(DateTime.Now + TimeSpan.FromSeconds(CacheDuration));
Response.Write(DateTime.Now.ToString());
}
Then when you add the UserControl, mine is named Cached, you could do this.
var cachedUserControl = new Cached {CacheDuration = 5};
Page.Controls.Add(cachedUserControl);

You can sue Response.Cache.SetExpires(DateTime DateTime); for that. Some useful infor here as well How to enable ASP.NET output caching programmatically.

Related

How to assign the value of user control property to aspx or codebehind in VB?

I have a user control with a public property which updates each time when a date from my calender(part of user control) is selected. Now I need to bring this value to page on which this user control is kept. How to do this.
I tried bringing the property value on page load event of aspx.vb(master page on which user control is present) but couldn't do it as page load is happening first and user property is loading next(null reference exception).
i tried this on page load of aspx hdnPPSeq.Value = PPCalender1.test1.ToString
Please share ideas to bring this value to aspx or codebehind in vb.
Create a method in usercontrol, which will return property value.
public partial class PassPropertyToPage : System.Web.UI.UserControl
{
string strSelectDateTime;
public string SelectedDateTime
{
set { strSelectDateTime = value; }
get { return strSelectDateTime; }
}
protected void Page_Load(object sender, EventArgs e){}
public string GetDateTime()
{
strSelectDateTime = <calendar value>;
return strSelectDateTime;
}
}
And in page, call the method to get the value:
public partial class AccessUserControlProperty : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Response.Write("DateTime selected in page: " + PassPropertyToPage1.GetDateTime() + "<br/>");
}
}

.net using and reaching public value

I wrote this code in .NET. When I want to change ‘s’ by clicking button2, it doesn’t change. I mean after clicking button2 and then I click Button1 to see the changes but nothing changes. How can I change and access the value of ‘s’ properly. What am I doing wrong?
public string s;
public void Button1_Click(object sender, EventArgs e)
{
Label1.Text = s;
}
public void Button2_Click(object sender, EventArgs e)
{
s = TextBox1.Text;
}
You need to understand how web applications work.
In each post back an instance of the class that handles the page is loaded, so when you click on button 1, the page does a post back and loads again, so this way the variable s isn't loaded with your content.
To make this code work, you need to save the S values on the page viewstate.
try replacing "public string s;" with this:
public string s
{
get { return (string)ViewState["myValue"]; }
set [ ViewState["myValue"] = value };
}
More Information about Page Life Cycle at: http://msdn.microsoft.com/en-us/library/ms178472(v=vs.100).aspx

Store and transfer values in a ascx control

I have a problem that I have been struggling with for some time, and it is regarding transfering values from one control to another.
Basically I have two .ascx controls. On control1: I have an email textbox called txtEmail. The txtEmail is used to save the email in the SQL table, and on update button click, I load Control2 that has a email textbox as well. I need the emailtext box from control1 to be available on email textbox on control2.
I have tried all kinds of different ways but to no avail. I even tried using delegates and events but I can't make it work.
Does anyone know how I can do this.
Regards
Please find below the code:
public event EventHandler Notify;
public string Email
{
get { return txtEmail.Text; }
set {Email= value ; }
}
//button that will handle the update
protected void btnUpdateDB_Click(object sender, EventArgs e)
{
var email = txtEmail.Text.ToString();
public BaseClass.BAL.MBAL m = new BaseClass.BAL.MBAL();
var s = new BaseClass.Controllers.m();
s.email=email;
if(m.save(s)!=0) txtMsave.Text="Saved....";
}
//second control
public void notifyEmailChange(object sender,EventArgs e)
{
txtUsername.Text = member1.Email;
}
protected void Page_Load(object sender, EventArgs e)
{
if(Page.IsPostBack)
{
member1.Notify += new EventHandler(notifyEmailChange);
}
}
public string email {
set { txtUsers.Text = value; }}
Maybe I am trivializing the problem, but if you are wanting to be able to read/write to the text box on each of the custom controls, just make a public property that reads and writes to the textbox on each of the two controls.
public string EmailAddress {
get {
return txtEmailAddress.Text;
}
set {
txtEmailAddress.Text = value;
}
}
Now the page that contains the two controls can read the email address from the first control and write it into the email address text box in the second control.
If I am misunderstanding the problem, let me know.
The way that I have done this in the past is to have
UserControl1 have a custom event called (for instance) Notify.
The containing control wires Notify to an EventHandler
When notify fires (on the update) the consuming event handler fires and this event handler updates the email on UserControl2
Might seem overengineered but because UserControl2 can't "see" UserControl1 I think this is the way to go
Example
In UserControl1
public event EventHandler Notify;
and within the update button click event handler
if(Notify != null)
{
Notify(this, new EventArgs());
}
In parent control
in Page_Load
ucUserControl2.Notify += new EventHandler(NotifyUserControl);
and to set the message
protected void NotifyUserControl(object sender, EventArgs args)
{
ucUserControl2.Email = ucUserControl1.Email;
}
You obviously need public properties in UserControls to expose the Email text

how to insert data within a calendar cell into a database

i have a calender and i was able to add text-box inside the cell using the day-render event but what i am trying to do is allow the user to add data to the text-box and then press add and the content is added to a database and showed inside that same text-box:
here is what i did:
protected void Page_Load(object sender, EventArgs e)
{
Calendar1.SelectedDate = DateTime.Now;
}
protected void update(object sender, DayRenderEventArgs e)
{
TextBox tb = new TextBox();
Button1.click += new EventHandler(insert);
e.Cell.Controls.Add(Button1);
e.Cell.Controls.Add(textBox2);
}
protected void insert(object sender, EventArgs e)
{
}
and i know how to insert the data but i am lost on how to identify it and output it back to the same text box
thanks
Well I'm not sure exactly what part you are lost on based on your question, so short of providing a complete working example I'll hit some of the main points:
1) To identify the data you are inserting, attach a date (and time if applicable) to the record. (Edit: are you looking for a mechanism to accomplish this? If so post your current DayRender handler code and Calendar markup).
2) To populate individual day data in a calendar, use Calendar.VisibleDate (to filter DB results) in a Page.Load handler to load a data structure (such as a List<T>) with day data for the entire month. Then in a Calendar.DayRender handler, add appropriate records from the structure to the e.Cell.
3) To cause the new results to show up on the first page refresh after insertion, you should be able to get away with using a Response.Redirect to the current page after insertion. This will cause the page generation process to restart, but you will lose ViewState.
Edit: Here is a basic prototype of what I tried to describe above. Note that you could pre-fetch into any enumerable data type, I use a List<T> here.
//Page code-behind
public partial class Default2 : System.Web.UI.Page
{
List<DataObject> liCurrentMonth = new List<DataObject>();
protected void Page_Load(object sender, EventArgs e)
{
liCurrentMonth = DataObject.GetCurrentMonth(Calendar1.VisibleDate);
}
protected void Calendar1_DayRender(object sender, DayRenderEventArgs e)
{
foreach (DataObject item in liCurrentMonth)
{
if (item.date == e.Day.Date)
{
Literal lit = new Literal();
lit.Text = item.text;
e.Cell.Controls.Add(lit);
}
}
}
}
//Data layer object
public class DataObject
{
public DateTime date { get; set; }
public string text { get; set; }
public static List<DataObject> GetCurrentMonth(DateTime currentdate)
{
//Get items from the db here, based on currentdate parameter
//and populate the List<DataObject>.
return new List<DataObject>();
}
}
I'm not sure you'll get this to work. Its the page viewstate that remembers the value entered into textboxes etc. Viewstate is created just before the page renders. The Calendar DayRender event is called during the calendars rendering, and hence after viewstate has done its thing. Therefore the viewstate mechanism is not aware of the existance of the textboxes and so will not track their content.
Perhaps you could assign each textbox an ID based on the month and day number, on postback you could check for this control ID in the Request.Form collection and do something with the data?

How to calculate the page index in grid view

I am using a set of codes for all web pages
grvcity.PageIndex + = 1;
to get the next page in grid view
I want to caluclate the page index where the currently is on . How to do it
GridView.PageIndex property both gets and sets the index of currently displayed page:
[BrowsableAttribute(true)]
public virtual int PageIndex { get; set; }
Therefore, the answer in your case should simply be:
int currentPage = grvcity.PageIndex;
Update
If you are talking about the PageIndexChanging event, here is a sample:
protected void grvcity_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
grvcity.PageIndex = e.NewPageIndex;
grvcity.DataBind();
}

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