To do this in the GUI style, click on the form of the page and then select the elements properties. Under the ASP.NET subheading, there is a form property called DefaultButton. Insert the button control id of the default button. This will essentially submit the form on enter (by performing the action on the specified button). The image to the left is an example of the form property section with a default button set to btnSetCookie. Note that for one reason or another, intellisense is not enabled on this property and you will have to manually type in the button control id.

Of course, you are not constrained to doing this in the GUI style. To submit a form on enter programmatically, simply find the form and insert the keyword defaultbutton=”BUTTON_CONTROL_ID_HERE”. Below is an example of how the above example would look programmatically.

<form id="frmTestForm" runat="server" defaultbutton="btnSetCookie">

function getUrlStringValue($urlStringName, $returnIfNotSet) {
  if(isset($_GET[$urlStringName]) && $_GET[$urlStringName] != “”)
    return $_GET[$urlStringName];
  else
    return $returnIfNotSet;
}

Let’s run through an example of how this function works. Assume we have the following url:

http://www.victorchen.info/index.php?firstName=Victor&lastName=Chen

If I am looking to find the string value of the first and last name, but return john or doe if the query variable firstName or lastName is not found, respectively. I would write the following:

$firstName = getUrlStringValue("firstName“, “john”);
$lastName = getUrlStringValue(”lastName“, “doe”);

In this example, we would expect to store $firstName to be “Victor” and $lastName to be “Chen”.

However, if the url arrives as (missing the lastName query string variable):

http://www.victorchen.info/index.php?firstName=Victor

We can expect to see $firstName as “Victor” and $lastName as “Doe”.

CS0433: The type exists in both [dll1] and [dll2]

The old dll temporary location was at C:\Windows\Microsoft.NET\Framework\v1.0.3705\Temporary ASP.NET Files and the new dll temporary location was at C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files. Note that these locations will vary depending on the Microsoft.NET framework version you are using.

My first thought was that the temporary location somehow got out of sync, so I decided to rebuild the solution, but this was unsuccessful. My next idea was the delete both temporary folders, but had problems because the folders were locked. The last thing I tried was to manually add a copy of the dll to the Solution’s bin folder and reference that specific copy. This fixed the problem!

private void exportDataTableToCsv(DataTable formattedDataTable, string filename)
{
DataTable toExcel = formattedDataTable.Copy();
HttpContext context = HttpContext.Current;
context.Response.Clear();

foreach (DataColumn column in toExcel.Columns)
{
context.Response.Write(column.ColumnName + “,”);
}
context.Response.Write(Environment.NewLine);
foreach (DataRow row in toExcel.Rows)
{
for (int i = 0; i < toExcel.Columns.Count; i++)
{
context.Response.Write(row[i].ToString().Replace(”,”, string.Empty) + “,”);
}
context.Response.Write(Environment.NewLine);
}

context.Response.ContentType = “text/csv”;
context.Response.AppendHeader(”Content-Disposition”, “attachment; filename=” + filename + “.csv”);
context.Response.End();
}

To call this function, simple create a C# LinkButton or Button Web Control. In your aspx page, your control should look similar to:

<asp:LinkButton ID=”lbToExcel” runat=”server”>Export To Excel</asp:LinkButton>

From here, the lbToExcel_Click function will call the Export to DataTable function exportDataTableToCsv defined earlier in this post. I would also advise making edits at this point to your DataTable by removing columns that were hidden in the GridView (or DataGrid). We want to pass a formattedDataTable.

If your page uses Ajax’s Update Panel controls, it is required to set the lbToExcel web control as a PostBackTrigger as opposed to an AsyncPostBackTrigger. To add a PostBackTrigger in Visual Studio 2008’s Ajax Update Panel, find the properties of the Update Panel. Under Behavior, find Triggers and choose to edit the Collection. Next, Click Add and from the Dropdown select PostBackTrigger. Next, you need to manually (without the aid of intellisense) type in the control name. In our case, the control name was lbToExcel. The result should be the code snippet example below:

<asp:UpdatePanel ID=”UpdatePanel1″ runat=”server”>
<ContentTemplate>
<asp:LinkButton ID=”lbToExcel” runat=”server”>Export To Excel</asp:LinkButton>
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID=”lbToExcel“>
</asp:PostBackTrigger>
</Triggers>
</asp:UpdatePanel>

Overall, this has worked flawlessly for me. If you have any problems, feel free to drop a line describing your challenges and I can attempt to give you a hand!

switch (lblDayOfWeek.Text)
{
case “1″:
lblDayOfWeek.Text = “Sunday”;
break;
case “2″:
lblDayOfWeek.Text = “Monday”;
break;
case “3″:
lblDayOfWeek.Text = “Tuesday”;
break;
case “4″:
lblDayOfWeek.Text = “Wednesday”;
break;
case “5″:
lblDayOfWeek.Text = “Thursday”;
break;
case “6″:
lblDayOfWeek.Text = “Friday”;
break;
case “7″:
lblDayOfWeek.Text = “Saturday”;
break;
default:
lblDayOfWeek.Text = “”;
break;
}

The final default is equivalent to else, which means if none of the cases match, the default route will be taken. The greatest advantage to using the switch statement is efficiency. When a swtich statement is called, only one comparison is made.

Note that the switch statement is not restricted to string or integer. It is also possible to use enum or virtually any other comparable variable.

Inconsistent accessibility: property type is less accessible than property

All this error message really means is that there is a public method that is illegally exposing a private property. Therefore, an easy fix (but not necessary the right one), is to change private property to public. I say this may not be the right approach because this may leave a security hole in your page and may not be how the page was originally designed.

The first step is to create an empty datatable. It would be perfectly legal to start with a datatable prepopulated with data. In this case, we are naming the Datatable, dt.

DataTable dt = new DataTable();

The next step is to create a new DataRow object. In this case, we are calling it “newRow”. The next step would be to initialize the DataRow object, which is the second line below:

DataRow myNewRow;
myNewRow = dt.NewRow();

Now that the DataRow has been created and initialized, simply add values to the object as you would an array. In the two examples below, we are adding values to two different columns in our row. We are first assigning the column with name customerId the integer value of 1. Secondly, we are assigning the column with name username a string johndoe. Repeat as needed.

myNewRow["customerId"] = 1;
myNewRow["username"] = “johndoe” ;

Finally, we want to add this newly created row (with two columns) to the originally blank datatable we created in the beginning.

dt.Rows.Add(myNewRow);

All the steps from above are put together in the example below:

DataTable dt = new DataTable();
DataRow myNewRow;
myNewRow = dt.NewRow();
myNewRow["customerId"] = 1;
myNewRow["username"] = “johndoe” ;
dt.Rows.Add(myNewRow);

With that you can now set this datatable as a DataSource and DataBind a GridView or any other similar C# control.

string myValue = Request.ServerVariables.Get(”foo“);

If you get the following error message: The name “Request” does not exist in the current context, try the following:

string myValue = System.Web.HttpContext.Current.Request.ServerVariables.Get(”foo“);

The first method can be dangerous, is easier because it is a non-interactive installation. It automatically assumes yes to all prompts.

yum -y update

The second method is safer and is exactly the same as the first method, except it will prompt you at specified parts of the installation process.

yum update

ENSURE RSH PACKAGES INSTALLED

The first step is to insure you have the correct packages installed. To do this, simply type the following in the terminal.

rpm -qa | grep -i rsh

The following should return two packages similar to:

rsh-server-0.17-25.3
rsh-0.17-25.3

If you are missing any of the above packages, run the code below to have the appropriate two rsh packages installed using yum.

yum install rsh*

EDIT FILE: /etc/xinetd.d/rsh
The most common changes are in red, though you should still confirm the rest of the file.

# default: off
# description:
# The rshd server is a server for the rcmd(3) routine and,
# consequently, for the rsh(1) program. The server provides
# remote execution facilities with authentication based on
# privileged port numbers from trusted hosts.
service shell
{
socket_type = stream
wait = no
user = root
log_on_success += USERID
log_on_failure += USERID
server = /usr/sbin/in.rshd
disable = no
}

EDIT FILE: /etc/xinetd.d/rlogin
The most common changes are in red, though you should still confirm the rest of the file.

# default: off
# description:
# Rlogind is a server for the rlogin program. The server provides remote
# execution with authentication based on privileged port numbers from trusted
# host
service login
{
socket_type = stream
wait = no
user = root
log_on_success += USERID
log_on_failure += USERID
server = /usr/sbin/in.rlogind
disable = no
}

EDIT FILE: /etc/xineted.d/rexec
The most common changes are in red, though you should still confirm the rest of the file.

# default: off
# description:
# Rexecd is the server for the rexec program. The server provides remote
# execution facilities with authentication based on user names and
# passwords.
service exec
{
socket_type = stream
wait = no
user = root
log_on_success += USERID
log_on_failure += USERID
server = /usr/sbin/in.rexecd
disable = no
}

EDIT FILE: /etc/securetty
The most common changes are in red, though you should still confirm the rest of the file.

console
vc/1
vc/2
vc/3
vc/4
vc/5
vc/6
vc/7
vc/8
vc/9
vc/10
vc/11
ttyS0
tty1
tty2
tty3
tty4
tty5
tty6
tty7
tty8
tty9
tty10
tty11
pts/0
pts/1
pts/2
pts/3
pts/4
pts/5
pts/6
pts/7
pts/8
pts/9
rsh
rlogin
rexec

RESTART THE RSH-SERVER SERVICE
To restart, one of the the following two commands below. One restarts the service while the other starts again.

/etc/init.d/xinetd start
/etc/init.d/xinetd restart