ASP.NET

Response.Redirect behavior

11-Dec-12 6:48

You need to read two MSDN articles. that will give you idea about how can you create regular expression,

and here it is,

http://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex.aspx[^]
http://msdn.microsoft.com/en-us/library/2k3te2cs%28v=vs.80%29.aspx[^]

Thanks
-Amit Gajjar (MinterProject)

AnalogNerd10-Dec-12 9:11

AnalogNerd

10-Dec-12 9:11

Given the following code in an .ASPX webforms application :

try
{
    // a bunch of code, database stuff, etc.

    Response.Redirect("somePage.aspx");
}
catch (Exception ex)
{
   // Error Logging
}
finally
{
    // object cleanup and disposal
}

I'm wondering if the code in the Finally block (or any code that might be outside of the whole try/catch) would ever be hit.

Doesn't the Response.Redirect() immediately redirect making any code that follows useless? Or do I just not understand how this works?

David Mujica10-Dec-12 10:01

David Mujica

10-Dec-12 10:01

Not trying to be a smart-ass, but why don't you just try it?

Place some dummy code in the finally block and see if it executes. (Use a break-point)

My hunch is that the finally code will execute. Also it may depend on which event the Response-Redirect is placed. (PageLoad, PageInit, ButtonClick, etc)

Post your results, so we all can learn. Java | [Coffee]

AnalogNerd10-Dec-12 10:16

AnalogNerd

10-Dec-12 10:16

I'm beyond mortified that I didn't think of that. Especially since after posting the question I ran the code to check something else, but putting a break point there just never occurred to me. Sigh | :sigh:

Ok, so thanks to David's suggestion I have an answer.

As it is written that code will throw an exception on the Response.Redirect with the following message:

Quote:
{Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack.}

However, it still does the redirect after going through the finally block.

Changing the Response.Redirect to

Response.Redirect("SomePage.aspx", false);

will save it from throwing the exception, but will still run the code in the finally and any code after it and then will do the Redirect.

Live and learn.

modified 11-Dec-12 9:26am.

Shameel10-Dec-12 21:28

Shameel

10-Dec-12 21:28

As you've already figured out, code in the finally block is guaranteed to execute no matter what (unless the runtime host decides otherwise or a system error forcefully terminates the process itself)

AmitGajjar11-Dec-12 6:54

11-Dec-12 6:54

Finally block will always execute, no matter if you redirect your page or throwing some exception.

Finally block will not execution on only Some Exceptions[^]

When you pass 2nd optional Boolean parameter, it indicate whether you would like to complete page execution or just want to redirect page and leave current execution.

Thanks
-Amit Gajjar (MinterProject)

ZurdoDev12-Dec-12 4:36

ZurdoDev

12-Dec-12 4:36

You already have your answer but to explain Response.Redirect a little more: It is telling the Response object to redirect the user to the new page. What happens is the client gets that message and then requests somePage.aspx. So, it roundtrips but your C# thread will finish. It's essentially just adding a property to the Response object.

Server.Transfer will still finish your C# thread (finally will still run) but the client will not roundtrip. Execution will stay on the server and go to somePage.aspx and execute it and send the Response object back to the client.

There are only 10 types of people in the world, those who understand binary and those who don't.

ERROR while updating image in database

AnalogNerd12-Dec-12 4:46

AnalogNerd

12-Dec-12 4:46

Very well put. Thanks ryanb31.

Ani199110-Dec-12 6:18

Ani1991

10-Dec-12 6:18

when i m trying to update image in sql database i m getting error as"Cannot bulk load. The file "System.Byte[]" does not exist."
my code is as follows.pls help.
protected void Button1_Click(object sender, EventArgs e)
{
{
if (FileUpload1.HasFile)
{
byte[] productImage = FileUpload1.FileBytes;

string constr = "Server=AOD257; Database=Edusocial;User ID=sa; Password=password";
string query = "UPDATE Profile SET [Pic] = (SELECT Pic.* from Openrowset(Bulk '" + productImage + "', Single_Blob) MyImage) where Id =11651658";

SqlConnection con = new SqlConnection(constr);
SqlCommand com = new SqlCommand(query, con);
com.Parameters.Add("@Pic", SqlDbType.Image).Value = productImage;

con.Open();
int result = com.ExecuteNonQuery();

con.Close();

if (result > 0)
{
Response.Redirect("Default.aspx");
}
}
else
{
lblmessage.Text = "Please Select Image File";
lblmessage.Visible = true;
}
}

}

jkirkerx10-Dec-12 10:37

10-Dec-12 10:37

I can't see how that would work, mixing unicode with bytes to enter into a blob.

"UPDATE Profile SET [Pic] = (SELECT Pic.* from Openrowset(Bulk '" + productImage + "', Single_Blob) MyImage) where Id =11651658";

versus

"UPDATE Profile SET [Pic] = productImage WHERE Id =11651658";

in which the latter is pure bytes from the file upload.

Ani199110-Dec-12 21:15

Ani1991

10-Dec-12 21:15

"UPDATE Profile SET [Pic] = '"+productImage+"' WHERE Id =11651658"

this query is working fine.but then image in image box is broked.its not been displayed.pls help.

Richard Deeming11-Dec-12 0:54

Richard Deeming

11-Dec-12 0:54

You're nearly there:

"UPDATE Profile SET [Pic] = @Pic WHERE Id = 11651658"

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

jkirkerx11-Dec-12 7:26

making a class with streamreader thread safe - perhaps using monitor or a singleton

11-Dec-12 7:26

I don't think you wrap a blob in single quotes, you use it like an integer or number.

The other post is correct, but he forgot to say that you use a parameter to store the data, and use the parameter again in your TSQL.

http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlparameter.aspx[^]

jkirkerx9-Dec-12 11:45

Re: making a class with streamreader thread safe - perhaps using monitor or a singleton

9-Dec-12 11:45

So I separated some write functions, that update a XML file into separate classes, that generate a thread in the background to open, update and write the XML file using streamreader and streamwriter.

So I'm new to threads on vb managed code, and just found that StreamReader is not thread safe. I did some research and one MSDN article says I need to wrap the streamreader in textreader and synchronize.

I did some more research, stumbled across monitor.enter and monitor exit, and the singleton class, so that only 1 instance of the class can run at a time.

So I have a file called "Landing.xml" and I'm interested in only have 1 instance of the class work the file at a time.

Just looking for suggestions, or help with implementing. Will post code is someone asks.

jkirkerx9-Dec-12 16:14

Display Images from a database in a tile view

9-Dec-12 16:14

Well I tried using monitor and so far so good. So I have like 15 of these class files that handle 1 xml file each, and they seem to be queuing up correctly, and waiting politely for the previous instance of itself to complete before firing again.

So the Yandex and Baidu bots have visited, and the updates were handled without error this time over the last 3 hour test period.

Well time will tell, will check the results again in the morning.

Still interested in the Singleton concept. Not quite sure how to implement it in vb

Member 94655649-Dec-12 5:42

Member 9465564

9-Dec-12 5:42

i want to retrieve images from a database and display them in a tiled view(at least three on a row) but i don't know how to go about that could someone please shed light on this for me?

Re: Display Images from a database in a tile view

Ali Al Omairi(Abu AlHassan)10-Dec-12 2:23

Ali Al Omairi(Abu AlHassan)

10-Dec-12 2:23

Use an HTTP Handler.

Help people,so poeple can help you.

linq connection in asp.net

JonBrynjar8-Dec-12 3:58

JonBrynjar

8-Dec-12 3:58

Hi all!

I have established a linq connexion with my database with this code behind.
And with manually set paging for 10 records.
data is shown in ListView.
How do I get the header sorting I'm using a linkbutton. Also I want to be able to insert a dropdownlist in the header. How do I receive this functionality.
With thanks in advance.

private void DisplayData(int startRow)
    {
      using (Origo.Vefur.Linq.dbMainDataContext db = new Linq.dbMainDataContext(Origo.WMMain.Helpers.Global.ConnectionString))
      {

        var empList = from el in db.owm_USERs
                      where el.showOnWeb == 1
                      select el;

        //ListView1.DataSourceID(employeeList);
        ListView1.DataSource = empList.Skip(startRow).Take(10);
        ListView1.DataBind();
      }
    }

My list view looks now like this

XML

<asp:ListView ID="ListView1" runat="server"
      onselectedindexchanged="ListView1_SelectedIndexChanged1"
      onsorted="ListView1_Sorted" onsorting="ListView1_Sorting">
      <LayoutTemplate>
        <table id="Table1" runat="server" class="TableCSS">
          <tr id="Tr1" runat="server" class="table-header">
            <th align="left"><asp:LinkButton ID="lnkID" CommandArgument="id" CommandName="Sort" Text="id" runat="server" /></th>
            <th align="left"><asp:LinkButton ID="lnkName" runat="server">Nafn</asp:LinkButton></th>
            <th align="left">
              <asp:dropdownlist runat="server" id="ddlWrokplace"
                  DataTextField="workplace" DataValueField='<%# Eval("workplace") %>' SelectedValue='<%# Eval("workplace") %>'></asp:dropdownlist>
            </th>

But neither the sorting links nor the dropdown list are working properly

Re: linq connection in asp.net

AmitGajjar11-Dec-12 7:00

11-Dec-12 7:00

Although i have never tried this but you can refer below links, it looks promising ...

Complete ListView in ASP.NET 3.5[^]

Discussion 1[^]

Discussion 2[^]

Thanks
-Amit Gajjar (MinterProject)

Change root path

#realJSOP8-Dec-12 3:40

#realJSOP

8-Dec-12 3:40

Is there a way to change or specify how virtual paths are resolved?

I'm creating a site on my machine, but for purposes of demonstration, I want to deploy it to a sub folder of an existing web site. So, on the web host, I have

wwwroot (which is the parent site)
wwwroot/demosite (which is the demo web site)

Of course, this means that a virtual path of "~/demosite.master" ain't gonna work, because that would resolve to "/demosite.master" instead of the desired "/demosite/demosite.master".

I tried using inline code, but of course that isn't allowed (some far-sighted MSoftie probably knew I was going to need to do this, and this is some sort of weird personal vendetta to prevent me from actually getting anything done).

What I want to do is to make the code change the various virtual paths used throughout the demosite, so that I don't have to remember to do it when I deploy to it's actual production server.

So, for localhost (when developing) and deployment onto the actual production server, I want to use the current virtual path, but for the demo version, I need to change the virtual path root.

Is that possible, and if so, how?

".45 ACP - because shooting twice is just silly" - JSOP, 2010
-----
You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
-----
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass." - Dale Earnhardt, 1997

Re: Change root path

Richard Deeming10-Dec-12 1:35

Richard Deeming

10-Dec-12 1:35

When you deploy the site, you need to make sure that the "demosite" folder is an application. In IIS Manager, right-click on the folder and select "Convert to Application". Your app-relative paths (~/demosite.master) will then resolve to the correct path.

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

Re: Change root path

#realJSOP10-Dec-12 1:42

#realJSOP

10-Dec-12 1:42

I'm not sure I can change that, since the deployment is to a web host.

I was actually hoping for a web.config approach, or some other technique.

Re: Change root path

AmitGajjar11-Dec-12 7:10