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I have a LinkButton in a DataList.
I also have a textbox in the same dataList.
The LinkButton is supposed to delete the message that a user posted. Meaning the logged in user posted a comment and he will be able to delete if he wants to his message. Only his messages all other messages will not have the Delete LinkButton.
How do I iterate through the DataList and only when it finds a LinkButton, detect if the username logged in posted messages that are stored in the database.
I use a Session for a username and Data Reader for database - dr[0]
Thanks in advance.
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Why iterate through the list? Use the CommandArgument property of the button to pass the id of message to your event handler.
only two letters away from being an asset
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Thanks for the response.
How would I pass the username of the person that posted a message through commantArgument and then compare that username with the session[username]. so that if the session[username] == to the username that posted, then delete button will be shown. the data including the username comes from a database which DataList retrieves iteratively.
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If your application is properly architected then the user who posted the message will be linked to it through the id in your datasource. So if you pass the id of the message you lookup the name and compare it.
only two letters away from being an asset
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so I pass the user name who logged in through the commandArgument?
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Read the replys  Pass the message ID and lookup information about the message, like username, from your datasource.
only two letters away from being an asset
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Ok. Thanks. I will try that.
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I think easy method is to use HyperLink control instead of LinkButton. Set the URL of HyperLink to something like deletemessage.aspx?messageId=someid. In the deletemessage.aspx, do the necessary validations and delete the message and return back to the previous page. This will help you not to iterate on DataList rows which will become slower if you have many rows in DataList.
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Thanks for responding. But there are other items in the DataList = the username of who posted, date, and message. That's why I chose the DataList to retrieve it from the database.
How would I use a hyperlink outside of the Data List so that it would be right below each message that has to be deleted?
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Albert83 wrote: But there are other items in the DataList = the username of who posted, date, and message. That's why I chose the DataList to retrieve it from the database.
I think you haven't got what I said. My point is to replace LinkButton with HyperLink button which will redirect to a particlular page and delete the supplied message. This is what CP is doing. You can see the Delete link points to a separate page which asks for the confirmation and delete it.
Albert83 wrote: How would I use a hyperlink outside of the Data List so that it would be right below each message that has to be deleted?
How come it will be right below of the each message if you put it outside of DataList? The LinkButton/HyperLink should be placed at the end of template column. So that it will come with each message.
If you are creating some sort of forums, I believe repeater will be the right control than DataList. You will have more control over the rendered HTML.
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N a v a n e e t h wrote: deletemessage.aspx?messageId=someid
Why?? Now you need another page, deletemessage.aspx, to handle what could be done in the same page, or passed to a controller and separated from your presentation.
only two letters away from being an asset
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But I need to show the Delete text under the approprite message first and the process the delete. So if I use the hyperlink how would it show where needed?
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Use a template to display each row. I think this project is bit beyond your level.
only two letters away from being an asset
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You are right. I had a feeling that OP is absolute beginner and it would be tough for him if I suggest handling the DataList event and doing all the processing. I felt redirecting to another page would be trivial and easy for him to understand. This is the reason for that suggestion.
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Actually I am far from a beginner. I tried the data list handling as follows but it only gets the first row everytime, and starts over. it never goes to the next record. I know the problem but don't know the solution.
What kind of template should I be using? Data List is a template.
Thanks again.
protected void DataList1_ItemDataBound(object sender, DataListItemEventArgs e)
{
foreach (DataListItem dlItem in DataList1.Items)
{
LinkButton lb = (LinkButton)dlItem.FindControl("deleteBtn");
using (SqlConnection sqlConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString))
{
sqlConnection.Open();
SqlCommand cmdRFullName = new SqlCommand("SELECT username FROM mediaComments ", sqlConnection);
SqlDataReader dr = cmdRFullName.ExecuteReader();
if (dr.HasRows)
{
while (dr.Read())
{
if (Session["user_name"] != dr["username"])
lb.Visible = false;
Response.Write("dr" + dr[0] + "<br />");
}
}
}
}
<asp:DataList DataKeyField="commentId" OnDeleteCommand="DataList1_DeleteCommand" ID="DataList1" RepeatLayout="table" runat="server" DataSourceID="ChalkDL">
<ItemTemplate>
<table width="500" cellspacing="0" cellpadding="5" border="0">
<tr>
<td><asp:LinkButton ID="lnkUser" runat="server" Text='<%# DataBinder.Eval(Container.DataItem, "username") %>'></asp:LinkButton></td>
</tr>
<tr>
<td colspan="1" width="240px" style="width: 240px; color: Black;" align="left" ><%# DataBinder.Eval(Container.DataItem, "commentText") %></td>
<td style="padding-top: 10px; color: Black;" align="right"><%# String.Format("{0:hh}:{0:mm}{0:tt} {0:MM}.{0:dd}.{0:yy}", DataBinder.Eval(Container.DataItem, "datePosted"))%></td>
</tr>
<tr>
<td style="padding-top: 10px;"><asp:LinkButton OnCommand="LinkButtonCommand" CommandArgument='<%# DataBinder.Eval(Container.DataItem, "username") %>' OnClientClick="return confirm('Are you sure you want to delete your post?');" Visible='<%# visible %>' runat="server" CommandName="delete" ID="deleteBtn" Text="Delete"></asp:LinkButton></td>
</tr>
<tr>
<td colspan="2"><hr /></td>
</tr>
</table>
</ItemTemplate>
</asp:DataList>
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Albert83 wrote: Actually I am far from a beginner.
Not from your questions and responses
Albert83 wrote: What kind of template should I be using?
See what I mean 
Albert83 wrote: ("SELECT username FROM mediaComments ",
in-line sql, another novice mistake
Albert83 wrote: I know the problem
So do I, it's over your head.
Try looking here[^] and reading about the events, like DeleteCommand and ItemDataBound
only two letters away from being an asset
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Ok. I am not an expert but have a lot of experience.
What would be a better solution to that ?
"SELECT username FROM mediaComments ",
in-line sql, another novice mistake
I looked at ItemDataBound before (Occurs when any button is clicked in the DataList control. )
The point is not to even show the delete button for the user who is not the poster of the comment.
As to templates, Repeater, and Data List can be templated. If not please explain what you mean.
Thanks.
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A better solution to in-line SQL? Ever heard of stored procedures?
Albert83 wrote: I looked at ItemDataBound before (Occurs when any button is clicked in the DataList control. )
Really? Then look again "Occurs when an item is data bound to the DataList control."[^]
You are using template, but using the methods incorrectly.
Albert83 wrote
"Response.Write("dr" + dr[0] + "<br />");"
;
You don't need this. Use the template to show your items, that's what it there for.
You should have enough information now, I suggest you read a little more and look at some of the many examples available. If you need any more, I'll have to start charging you. Where should I send the invoice?
only two letters away from being an asset
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Sure I heard of stored procedures, I use them when I find necessary.
"Response.Write("dr" + dr[0] + "
");" is for testing purposes. A lot of programmers do it when testing the results of the query.
All the items are templated actually.
You are right i mixed it with itemCreated.
Thanks for the help.
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Albert83 wrote: A lot of programmers do it when testing the results of the query.
 
A lot of novice programmers. Professionals use a debugger.
only two letters away from being an asset
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has nothing to do with level. It's a matter of preference.
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Mark Nischalke wrote: A better solution to in-line SQL? Ever heard of stored procedures?
It's a myth. IMO, nothing wrong with inline SQL other than the difficulty of recompiling code when the DB structure changes. This can be avoided by abstracting the table structure using views. So still you can write inline SQLs safely. Please do correct me if you felt I am wrong.
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N a v a n e e t h wrote: Please do correct me if you felt I am wrong.
Where do I start? This argument has been raised several times.
Inline doesn't allow for separation of the business logic from the presentations, which a good design does, and increases maintenance and development. 10 apps with the same SQL statement must each be changed, rather changing one stored proc. Worse yet, if the schema changes, say a table or column is renamed, all statements must be changed instead of changing one stored proc. Inline statements also don't allow the RDBMS to optimize the execution or otherwise cache it for better performance. Just few of the many reasons.
Then again, if you don't care about robust, well designed and performant applications, keep using inline statements.
only two letters away from being an asset
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That is true. But if you use a statement only once it's ok to use inline statement.
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And if that one statement is executed 1000 times, what does that do for the performance of your system?
only two letters away from being an asset
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