Purpose Of StringWriter - Usage?
Feb 18, 2010i would like to know what the StringWriter Class is about and when we should use it.
View 2 Repliesi would like to know what the StringWriter Class is about and when we should use it.
View 2 RepliesI am getting the following error with my GridView using StringBuilder/StringWriter: MyGridView of type 'GridView' must be placed inside a form tag with runat=server.
StringBuilder SB = new StringBuilder();
StringWriter SW = new StringWriter(SB);
HtmlTextWriter htmlTW = new HtmlTextWriter(SW);
MyGridView.RenderControl(htmlTW); //error here
string s = SW.ToString();
I am also using a MasterPage, which I believe has a lot to do with why I am getting this error. Is there a work around?
i am trying to write a gridview to an excell file, but i get the error: The type or namespace name 'StringWriter' could not be found (are you missing a using directive or an assembly reference?)
my code is:
protected void Button1_Click(object sender, EventArgs e)
{
//Clear content of buffer stream
Response.Clear();
//Set the type and filename
Response.AddHeader("TITLE", "TITLE.xls");
Response.Charset = "iso-8859-2";
Response.ContentType = "application/vnd.xls";
// Add the HTML from the GridView to a StringWriter to write it out later
StringWriter sw = new StringWriter();HtmlTextWriter htw = new HtmlTextWriter(sw);
GridView1.RenderControl(htw);
//Write out the data
Response.Write(sw.ToString());
Response.End();
}
what is the use of delegates. why we use delegates.
View 1 Replieswhat i want to do is to get the current ip i have (with a site as, http://whatismyip.com/) and send it to paypal sandbox so i can get a response (of course i haven't started the paypal code but i first need to be able to get a communication from paypal,non?)Ok the problem is that if i start a new web site on IIS, hit the current ip, i get my router administration console as a response.I have tried to change the port on a new site to 81 or 82 or 83 but i get a page not found.
View 11 Replies<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" onrowediting="GridView1_RowEditing">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:Button ID="btnEdit" runat="server" Text="Edit" CommandName="Edit" />
<asp:Label ID="lblFirstColumn" runat="server" Text='<%# Eval("FirstColumn") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:Label ID="lblEditMode" runat="server" Text="This is Edit mode"></asp:Label>
</EditItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
protected void Page_Load(object sender, EventArgs e)
{
DataTable dt = new DataTable();
dt.Columns.Add("FirstColumn", typeof(int));
dt.Rows.Add(100);
GridView1.DataSource = dt;
if (!IsPostBack)
GridView1.DataBind();
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
GridView1.DataBind();
}
If I change if (!IsPostBack) GridView1.DataBind(); to GridView1.DataBind(); and try to put GridView into Edit mode by clicking btnEdit, then I get the exception: Invalid postback or callback argument. Event validation is enabled using in configuration or <%@ Page EnableEventValidation="true" %> in a page. For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation. But if I set EnableEventValidation to false, then GridView1 won't enter edit mode ( ie - GridView1_RowEditing doesn't get called ). BTW - same problem also occurs with other databound controls ( DataList, DetailsView ) Page. EnableEventValidation gets or sets a value indicating whether the page validates postback and callback events. When the ableEventValidation property is set to true, ASP.NET validates that a control event originated from the user interface that was rendered by that control. A control registers its events during rendering and then validates the events during postback or callback handling.
a) Why must postback and callback events be evaluated? and how exactly does evaluation happen?
b) Why would calling GridView1.Databind() on each postback cause exception when trying to put it into edit mode?
c) I also don't see any reasons why disabling EnableEventValidation prevents GridView from entering edit mode?! Thus why did.
Can anyone tell me what does CAPTCHA do as far as security issue is concerned?Registration form of many sites have this field but how it works?
View 5 Repliesi want to know what is purpose of using masterpage?
View 5 Repliesfound a .gpState file in the folder,What is the purpose of gpState file?
View 2 Repliespurpose and mechanisms of the postback event? I am becoming very confusined when reading and am hoping that someone could explain it to a beginner.
View 17 RepliesWhat is the purpose of BrowserFile1.browser?
How to use it?
What is the purpose of Handler (.ashx files) and what is the use ?
can i get any sample ?
What is the purpose of the PropertySpecified pattern used by XML Serialization ?
View 1 RepliesI have a problem with URL of my application..................
I want to rewrite my url for security purpose......Like....
suppose my application URl is .....http://localhost/MyApplication/Product.aspx
But i want to change this url with......... http://localhost/MyApplication/MyProducts
In documentation I have read:
„Use the PostBackTrigger control to enable controls inside an UpdatePanel to cause a postback instead of performing an asynchronous postback."
I made simple application and I do not see difference between using PostBackTrigger and standard postback.
I have three buttons: two inside update panel and one outside update panel. When I click btnUpdateAsync in event handler I set text property of lblUpdatePanel and lblNoUpdatePanel and only lbl that is inside update panel is chaned if web browswer - so this is ok.
Whant I click btnUpdateInUpdatePanelSync all page is refreshed and both lablels are changed in web browser.
When I click btnUpdateOutsideUpdatePanel I see the same behavior.
If I used button that is not associated with PostBackTrigger I would get the same behavior - so what is the purpose of PostBackTrigger?
This is my app:
[Code]....
protected void Page_Load(object sender, EventArgs e)
{
}
protected void LinkButton1_Click(object sender, EventArgs e)
{
}
protected void btnUpdateAsync_Click(object sender, EventArgs e)
{
lblUpdatePanel.Text = "btnUpdateAsync_Click";
lblNoUpdatePanel.Text = "btnUpdateAsync_Click";
}
protected void btnUpdateInUpdatePanelSync_Click(object sender, EventArgs e)
{
lblUpdatePanel.Text = "btnUpdateInUpdatePanelSync_Click";
lblNoUpdatePanel.Text = "btnUpdateInUpdatePanelSync_Click";
}
protected void btnUpdateOutsideUpdatePanel_Click(object sender, EventArgs e)
{
lblUpdatePanel.Text = "btnUpdateInUpdatePanelSync_Click";
lblNoUpdatePanel.Text = "btnUpdateInUpdatePanelSync_Click";
}
i have to implement for online payment getting for donation for a social community
View 1 RepliesDuring a recent interview the following question was asked.
- A Master page which contains
- An ASPX web form page which contains
- A Web User Control inside the page which contains
- A button to fire some code in a button_click event
The Init Event will fire (Inner Most to Outer Most)
aspx.page Begin Init
-> Inside user control Page_Init
-> Inside master page Page_Init
-> Inside lifecycle page Page_Init
aspx.page End Init
and Load Event will fire
aspx.page Begin Load
-> Inside lifecycle page Page_Load
-> Inside master page Page_Load
-> Inside user control Page_Load
aspx.page End Load
Why does ASP.NET framework support different execution order in Load() and Init().This was the question asked in interview.I have no idea about what the interviewer expecting from me.
If you have a very large stored procedure, is it okay to just use the commands just once in the script?
ANSI_NULLS ON and QUOTED_IDENTIFIERS ON?I really don't understand the purpose of these commands?
What is the purpose and proper use of the max-length property on text fields?
The application I'm working on limits numeric fields to 6 characters... which doesn't work very well for entering millions of dollars... which is why I'm "fixing" it.
can anyone make it clear the main purpose of action attribute of form tag in html page?
View 2 RepliesWe are going to write an entire new application for a reservation system. In this system experts specify their free time in elaborated calendar and users seek them through searched and finally reserve the expert and his time.
We prefer to find an open source program like this and try to evolve it instead of creating it from scratch. In this manner our time is saved and that open source program will be completer too.
How server will detect the specific user, by the formsAuthentication cookie.
View 3 RepliesWhat is the purpose of adding a try catch condition that simply throws the Exception?
Sample Code (Note: The db object is proprietary code that simply uses ADO.Net):
[Code]....
I always have problem with the conception of flush who knows exactly what it means eg:
[Code]....
i want to make some questions about asp.net MVC,actually,i am not familiar with web developing.
But,i am assigned for web part.we are using like this.first,we create get set
properties for person data
public class Person
{
public int personID {get;set;}
public string personName {get;set;}
public string nric {get;set;}
}
and then after login,we put data in that class and we use RedirectToAction method like this,
return RedirectToAction("profile","person",new { personID = Person.personID});
it's working normally,but,parameter are shown at URL,how i hide them and also can i hide action name?