convert url to links in C# using Regex

public string ConvertUrlsToLinks(string msg)
{
string newMsg = "";

string regex = @"((www\.|(http|https|ftp|news|file)+\:\/\/)[_.a-z0-9-]+\.[a-z0-9\/_:@=.+?,##%&~-]*[^.|\'|\# |!|\(|?|,| |>|<|;|\)])";
Regex r = new Regex(regex, RegexOptions.IgnoreCase);
newMsg = r.Replace(msg, "$1").Replace("href=\"www", "href=\"http://www");

string emailRegex = @"(([a-zA-Z0-9_\-\.]+@)[_.a-z0-9-]+\.[a-z0-9\/_:@=.+?,##%&~-]*[^.|\'|\# |!|\(|?|,| |>|<|;|\)])";
Regex r2 = new Regex(emailRegex, RegexOptions.IgnoreCase);
newMsg = r2.Replace(newMsg, "$1");

return newMsg;
}

Form does not get value from readonly fields

To fix this, don't put readonly property for the controls by default, do it programatically. This has something to the storage of values for disabled properties. Apparently .NET does not store the value of disabled controls and hence does not pass the value on.

txtStartDate.Attributes.Add("readonly", "readonly");
txtExpDate.Attributes.Add("readonly", "readonly");

Measuring Execution Time

DateTime startTime = DateTime.Now;
Console.WriteLine(startTime);

Javascript Popup with Custom Controls in GridView ASP.NET

Prior to the earlier posting which describes how to use a custom control, the following codes describe how to use a custom control to launch a javascript function. In this case, to start a popup window by clicking on a link from the gridview table.

The codes are as follows:
<asp:TemplateField>
<HeaderTemplate>Manage</HeaderTemplate>
<ItemTemplate>
<asp:HyperLink NavigateUrl='<%# DataBinder.Eval(Container,"DataItem.class_id", "javascript:window.open(\"classstudents.aspx?id={0}\",\"mywindow\",\"menubar=1,resizable=1,width=400,height=500\");") %>' Text="Manage" runat="server" Target="myBuffer"></asp:HyperLink>
</ItemTemplate>
</asp:TemplateField>

The steps as usual are:
1. Create the objectdatasource
2. Creat the grdiview
3. Bind the objectdatasource to the gridview
4. Insert a TemplateColumn (when you select the grid and click edit column)
5. The templatecolumn should contain something liek the code above.
6. Done!

Take note that for javascript to work, it should be contained with a single quote. And if you need to display the quotes in javascript within asp.net, the escape character for asp.net C# is a backslash /

ASP.NET Custom Controls inside Gridview

The gridview is one of asp.net's most versatile function. Best used if you need to perform operations like create read, updated, remove (CRUD). Datalist would be good for CRUD as well. Simply because its as easy as just clicking around with minimal programming involved. Rule of the thumb is:

CRUD: gridview, datalist
CRUD: detailsview (used really for 1 page paging purpsoe)
CR: listview, repeater

But adding a custom control i.e. placing your own dropdownlist inside a gridview can be tricky. Its not as simple as just binding an object as per normal. The codes are as follows:
<asp:TemplateField>
<HeaderTemplate>Active?</HeaderTemplate>

<ItemTemplate>
<asp:Label id="lblClass" runat="server" Text='<%# returnYesNoValue(DataBinder.Eval(Container,"DataItem.active", "{0}")) %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:DropDownList id="ddlActive" SelectedValue='<%# Bind("active") %>' runat="server">
<asp:ListItem Value="1">Yes</asp:ListItem>
<asp:ListItem Value="0">No</asp:ListItem>
</asp:DropDownList>
</EditItemTemplate>
<HeaderStyle BorderStyle="None" />
<ItemStyle BorderStyle="None" />
</asp:TemplateField>

Steps:
1. Create an objectdatasource and link it with the a query from an XSD datafile.
2. Create a gridview and link it with the objectdatasource
3. Insert bound fileds and then insert the template fields
4. Go into the HTML code and then key in the codes above for the template area
5. As you can see its 'label' for viewmode and 'dropdownlist' for editmode
6. Make sure you bind the records with the value from db, and everything should work automatically.

Upload document in .NET C#

Very simply, there are two parts to this, storing in inside DB and retrieving for display. This program works for C# + MS SQL. Before everything I assume that you created a table inside the database with a field picture with datatype image.

Part I: Storing in Database
a.) setup an input file with the name UploadFile.
<input id="UploadFile" type="file" runat="server">

b.) setup a button with the name btnUpload
<asp:imagebutton id="btnUpload" onclick="btnUpload_Click" runat="server" height="29" width="150" imageurl="images/buttons/upload_long.jpg"></asp:imagebutton>

c.) setup code behide for the button to be
if (Page.IsValid) {
String userId = Session["authenticated_userid"].ToString();
Stream imgStream = UploadFile.PostedFile.InputStream;
int imgLen = UploadFile.PostedFile.ContentLength;
byte[] imgBinaryData = new byte[imgLen];
int n = imgStream.Read(imgBinaryData, 0, imgLen);
DB.userTableAdapter aAdapter = new // you need to set this up in your own DB.xsd
DB.userTableAdapter();
int rowsAffected = aAdapter.UpdatePicture(imgBinaryData, int.Parse(userId));
if (rowsAffected > 0) {
Response.Redirect("home.aspx"); // go back to same page
}
}

Part II: Retrieving stored image from DB
1.) Create a file call getImage.aspx and inside Page Load

protected void Page_Load(object sender, EventArgs e) {
String userId = Session["authenticated_userId"].ToString(); // get your own identified
DB.userTableAdapter aAdapter = new DB.userTableAdapter();
byte [] temp = aAdapter.GetPicture(int.Parse(userId));

if (temp == null) // in case we find nothing in db {
Stream s = File.OpenRead(Server.MapPath("images\\portrait.jpg"));
temp = new byte[s.Length];
s.Read(temp, 0, (int)s.Length);
Response.BinaryWrite(temp);
s.Dispose();
s.Close();
}
Response.BinaryWrite(temp);
}

2.) Wherever you want to show you image, just call the image as per normal
i.e. <img src="http://www.blogger.com/getImage.aspx" />

Done! Enjoy.

ASP.NET (C#) unable to ENTER to submit form

The best way to solve this is to do the following

1. Create a login function. i.e.
protected void login() {
// get database connection
// get variables from form
// check if correct, set session variable, redirect
// else, display error, return to form
}

2. In page load, use the following code:
If (Page.IsPostBack()) {
login();
}

Viola! Weird bug in ASP.NET i read. But yah, Page.IsPostBack fixes it all.