ASP.NET

4-Mar-09 5:12

Hello everyone ,
I have a treeview with special nodes (i wanted to store extra information in them) inheriting TreeNode

public class TreeNodeWithInfo : TreeNode
{.....
}

When i add chils , i do it like this :

TreeNodeWithInfo tnGroup = new TreeNodeWithInfo("sdkh", 1);
       TreeView1.Nodes.Add(tnGroup);
      ...

But after a button click , when i try to acces the extra information by downcasting ,

protected void Run_Click(object sender, EventArgs e)
    {
    ...
    ManageTree((TreeNodeWithInfo) TreeView1.Nodes[0]);
     ...
     }
i get a invalid cast exception . The TreeView1.Nodes[0] still has the right information (the one correspongind to the base class , the TreeNode ) but it seems that it's not an instance of TreeNodeWithInfo anymore ..
if i do this in  Run_Click 
<pre>  Response.Write(TreeView1.Nodes[0] is  TreeNodeWithInfo);

i get a "False" . but if i do the same thing in Page_Load , i get True ...

Can anyone help me out ?

Thank You !

TerRO_GirL4-Mar-09 5:14

4-Mar-09 5:14

Sorry for the bad tags , but i can 't edit it now , i dont know why Frown | :(

Viral Upadhyay4-Mar-09 8:02

Viral Upadhyay

4-Mar-09 8:02

hi, What i understand is TreeView takes TreeNode as a Child.
So if you inherit TreeNode to some other object say TreeNodeWithInfo
and add it TreeView will not take extra Property you set.
Also when you access node from TreeView it will
set the node as TreeNode not TreeNodeWithInfo i.e. TreeView cast node
as TreeNode not you New Inharit Node.
So the bottom Line is I think your logic will not work.
Sorry If i m not right.

Thanks
Viral

Viral
My Site
Tips & Tracks

TerRO_GirL4-Mar-09 8:04

4-Mar-09 8:04

Thank you for you answer !
But i think it actually has to do with inheritance , because in the page_load , after i set the nodes as TreeNodeWithInfo , it recognises it as a TreeNodeWithInfo , but at postback it becomes just a TreeNode .
I'm kinda lost Smile | :)

Viral Upadhyay4-Mar-09 8:12

Viral Upadhyay

4-Mar-09 8:12

May be you are right!!
When You Bind this Tree? In Page Load?
As When You accessing The TreeView You will Get a Object as TreeNode.
I am Bit Confuse too. Sniff | :^)

Viral
My Site
Tips & Tracks

Jörgen Andersson4-Mar-09 10:00

Jörgen Andersson

4-Mar-09 10:00

Have you also created TreeNodeCollectionWithInfo and TreeViewWithInfo?
Because TreeView is still using TreeNodeCollection which uses the old TreeNode. And that's probably the reason for the invalid cast exception

TerRO_GirL4-Mar-09 10:34

How to update Content of Exel sheet [modified]

4-Mar-09 10:34

Well , i haven't created a TreeNodeCollection .. But in Page_Load , the inheritance works perfectly . Weird stuff . Anyhow , i've managed to store the information in treenode.Value and i've given up on the TreeNodeWithInfo .
Thank you anyhow , guys !
Best luck !

Member 46590014-Mar-09 3:09

Member 4659001

4-Mar-09 3:09

In One of my page i need to read the data from Exel Sheet ,
and After reading the content form it I need to delete the content of Exel Sheet
(means i need to delete all rows it contain

I have done till how to read data from exel , Now i need to blank it
so Plz Guide me how to Blank Exel sheet

Well for deleting i used a function

private void call1()
{
string connectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\\OrderHeader.xls;Extended Properties=""Excel 8.0;HDR=YES;""";

DbProviderFactory factory = DbProviderFactories.GetFactory("System.Data.OleDb");

using (DbConnection connection = factory.CreateConnection())
{
connection.ConnectionString = connectionString;

using (DbCommand command = connection.CreateCommand())
{
command.CommandText = "Delete from [OrderHeader$]";

connection.Open();

command.ExecuteNonQuery();
}
}

}

But it is giving error msg
Deleting data in a linked table is not supported by this ISAM.

Raghvendra

modified on Wednesday, March 4, 2009 9:29 AM

Re: How to update Content of Exel sheet

Jörgen Andersson4-Mar-09 9:39

Jörgen Andersson

4-Mar-09 9:39

You can't do that, Excel isn't a relational datasource.
You can delete values in fields (cells).
But you can't delete an entire record at once.

how to use the chromeless player to play the video?

keyur satyadev4-Mar-09 1:23

keyur satyadev

4-Mar-09 1:23

hi.
i want to use the chrome less player to play the video.

i have one text box and button. in text box any one can put the URL of video file.
when click on the button the video file should be play in chromeless player.

how this can be achieved?

Re: how to use the chromeless player to play the video?

N a v a n e e t h4-Mar-09 1:28

N a v a n e e t h

4-Mar-09 1:28

How about reading the API reference[^]?

Smile | :)

Navaneeth

How to use google | Ask smart questions

installing visual source safe

thapaswi reddy4-Mar-09 1:06

thapaswi reddy

4-Mar-09 1:06

Hi Experts.
Can any one let me know how to install the visual source safe.....
thanks in advance

N a v a n e e t h4-Mar-09 1:07

N a v a n e e t h

4-Mar-09 1:07

Hi,

This is ASP.NET forum and your question has nothing to do with ASP.NET. Please check the microsoft forums for VSS.

Navaneeth

How to use google | Ask smart questions

thapaswi reddy4-Mar-09 1:15

thapaswi reddy

4-Mar-09 1:15

thanx buddy

Christian Graus4-Mar-09 9:45

Christian Graus

4-Mar-09 9:45

Just to add - you run the installer. How can a developer ask such a question ?

Christian Graus

Driven to the arms of OSX by Vista.