December 12, 2011 08:15 by
ScottIn this tutorial, I will show you how to setting up your .NET web application to use MySQL as your ASP.NET Membership Provider.
1. Download and install MySQL Connector/Net 5.2.1 or later version
2. Add a reference to MySQL.Web to your web application.
C:\Program Files\MySQL\MySQL Connector Net 5.2.1\Web Providers\MySql.Web.dll
3. Add the autogenerateschema=”true” attribute. Since the MySQL database schema wasn’t automatically created for me, I ended up using the autogenerateschema attribute. The attribute will signal the MySQL provider to build (or upgrade) the database schema.The MySQL 5.2.1 release notes state the following…
Using the new provider schema
=============================
For this release. the only way to upgrade a given server to the new schema is to
add a configuration option for one of your providers. The option is ‘autogenerateschema’.
By setting this to true, the provider will silently upgrade the server to the new schema.
Please note that there is no reversing of this procedure so please just do this on test
setups and not on your production systems.
Personally, I found it easiest to just add autogenerateschema=”true” to my machine.config on my development machine (as opposed to web.config) and it’s under providers…
<membership>
<providers>
<add name=”MySQLMembershipProvider” autogenerateschema=”true” ….
</providers>
Save the changes.
4. Edit your web application’s web.config.
<connectionStrings>
<remove name=”LocalMySqlServer”/>
<add name=”LocalMySqlServer” connectionString=”Datasource=localhost;Database=DB;uid=Username;pwd=Password;”
providerName=”MySql.Data.MySqlClient”/> </connectionStrings>
Then, save the changes.
5. Build your Web Application.
6. Config your web application.
Under the ASP.NET Web Site Administration Tool provider tab, click “Select a Different Provider (advanced)” and change the provider to MySQLMembershipProvider.
At this point, you should be able to use MySQL as your ASP.NET Membership and Role Provider (the tables will be automatically built for you).
After the tables are built, you’ll want to setup your web application’s web.config (using your machine.config as a template) so that you will have access to all of the membership provider settings.
December 5, 2011 08:19 by
ScottSometimes, we may want to add some ListItem that are not clickable or selectable in ASP.Net DropDownList. The non selectable items will be an informational list items that may help users to understand the items. For example, consider a DropDownList that has list of states of different country. It will be user friendly if we have a non selectable country name before populating the list of states under that country. Something like below,
The below jQuery code will help you to do the same,
<script src="_scripts/jquery-1.4.1.min.js" type="text/javascript"></script>
<script type="text/javascript">
$(function() {
$("#<% =DropDownList1.ClientID %> > option[value=Country]").attr("disabled", "disabled")
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True"
onselectedindexchanged="DropDownList1_SelectedIndexChanged">
<asp:ListItem Text="Select your state" Value=""></asp:ListItem>
<asp:ListItem Text="India" Value="Country"></asp:ListItem>
<asp:ListItem Text="-Karnataka" Value="1"></asp:ListItem>
<asp:ListItem Text="-TamilNadu" Value="2"></asp:ListItem>
<asp:ListItem Text="-Maharastra" Value="3"></asp:ListItem>
<asp:ListItem Text="-Kerala" Value="4"></asp:ListItem>
<asp:ListItem Text="United States" Value="Country"></asp:ListItem>
<asp:ListItem Text="-Alabama" Value="5"></asp:ListItem>
<asp:ListItem Text="-Alaska" Value="6"></asp:ListItem>
<asp:ListItem Text="-California" Value="7"></asp:ListItem>
<asp:ListItem Text="-Florida" Value="8"></asp:ListItem>
</asp:DropDownList>
The above jQuery code will disable all the list items that have Country as value and thus making it non selectable.
Happy Coding!!
December 2, 2011 05:46 by
ScottSometimes when you browse to an .aspx page, you may receive one of the following error messages:
Could not load type 'Namespace.Global'.
-or-
Could not load type 'Namespace.PageName'.
In this turorial I will show you how to fix it. This is caused by These errors occur if the .aspx page or the Global.asax page contains a reference to a code-behind module and if the application has not been built.
SOLUTION
· Use the C# command line compiler (CSC.exe) to run the following command:
csc /t:library /r:System.web.dll /out:mydll.dll myfile.cs
· In Microsoft Visual Studio .NET, click Build on the Build menu.
Hope it help
November 21, 2011 05:19 by
Scott
November 18, 2011 07:51 by
ScottToday I would like to discuss an interesting feature that is available only in ASP.NET4. It is primarily used in MVC3 applications.
ASP.NET 4.0 comes with a Encoded Expressions <%: expression %> that will automatically convert string into html encoded. Now we can replace all occurrences of <%= %> with <%: %>.
SO what is the difference between these two? Are they same?
No they are not. The main difference is when you use the new syntax our code get encoded. Any html script in side do not gets executed by the browser.
It is just treated as content. In the previous versions you might be using Server.HtmlEncode(<%=expression %>).
So this new syntax does exactly same function as this method. We can use HtmlString type to indicate encoding is unnecessary.
Proof of Concept
I have created a Test method that returns string and that string has some HTML characters like < > to be encoded
public static string Test()
{
return "alert('Hello World!!! returns javascript'); HTML Encoded expression";
}
Now add 2 aspx pages. In the first page add this code.
<DIV>
<form id="form1" runat="server">
<strong><%: Test()%></strong>
</form>
</div>
</DIV>
Now In the Second aspx page use this syntax
<DIV>
<form id="form1" runat="server">
<strong><%= Test()%></strong>
</form>
</div>
</DIV>
Run this pages on the browser one after the other. Now if you observe, first page gives a just text where as 2nd page is not encoded it returns the script alert message along with text . And look at the viewsource you can see the difference exactly.
Advantages
- General security threats for ASP.Net Web applications are Cross-site script injection attacks and HTML encoding attacks. This feature is nice handy way to eliminate javascript injection in your web applications.
- Now it is easy to replace <%=exp %> to <%:exp%> and make your code or data more secured.
- Now We do not need to specify Validate-Request to validate HTML Scripts in ASP.NET, which you may be doing it in web.config or pagelevel
Is it not so interesting?. So start playing with the feature.
Hope this helps. Let me know if any questions are clarifications.
November 11, 2011 06:08 by
Scott
November 8, 2011 05:18 by
ScottIn this tutorial, I will show you how to connect to MySQL Server with .NET in C# or ASP.NET. What requirements do you need?
1. Please download MySQL Connector/Net.
2. After you add a reference to your project, it is probably in C:\Program Files\MySQL\MySQL Connector Net 5.0.7\Binaries\.NET 2.0 folder, add the MySql.Data.dll file as a reference.
3. Make your connection string, the following code will shows a standard MySQL connection string.
using MySql.Data.MySqlClient;
public static string GetConnectionString()
{
string connStr =
String.Format("server={0};user id={1}; password={2};
database=yourdb; pooling=false", "yourserver",
"youruser", "yourpass");
return connStr;
}
4. Then create an instance from MySql.Data.MySqlClient.MySqlConnection as shown below.
MySql.Data.MySqlClient.MySqlConnection mycon
= new MySqlConnection( GetConnectionString());
5. Then try to open the MySQL connection.
if(mycon .State != ConnectionState.Open)
try
{
mycon .Open();
}
catch (MySqlException ex)
{
throw (ex);
}
Simple right?? J
October 10, 2011 07:21 by
ScottC# 4.0 supports Dynamic Programming by introducing new Dynamic Typed Objects. The type of these objects is resolved at run-time instead of compile-time. A new keyword dynamic is introduced to declare dynamic typed object. The keyword tells the compiler that everything to do with the object, declared as dynamic, should be done dynamically at the run-time using Dynamic Language Runtime(DLR). Remember dynamic keyword is different from var keyword. When we declare an object as var, it is resolved at compile-time whereas in case of dynamic the object type is dynamic and its resolved at run-time. Let’s do some coding to see advantage of Dynamic Typed Objects :)
A year back I wrote a code of setting property of an object using Reflection:
1: Assembly asmLib= Assembly.LoadFile(@"C:\temp\DemoClass\bin\Debug\DemoClass.dll");
2: Type demoClassType = asmLib.GetType("DemoClass.DemoClassLib");
3: object demoClassobj= Activator.CreateInstance(demoClassType);
4: PropertyInfo pInfo= demoClassType.GetProperty("Name");
5: pInfo.SetValue(demoClassobj, "Adil", null);
Notice line 3-5 creates instance of ‘demoClassType’ and set property ‘Name’ to ‘Adil’. Now with C# 4.0 line # 3-5 can be written as simple as:
dynamic dynamicDemoClassObj = Activator.CreateInstance(demoClassType);
dynamicDemoClassObj.Name = "Adil";
Simple isn’t it? Let’s see a slide from Anders Hejlsberg’s session at PDC 2008:
From the above slide, you can call method(s) such as x.ToString(), y.ToLower(), z.Add(1) etc and it will work smoothly :)
This feature is great and provides much flexibility for developers. In this post, we explore the dynamic typed object in C# 4.0. We will explore dynamic in detail and other features as well in the coming posts. Of course there are pros and cons of dynamic programming as well but where C# is going is something like having features of both static languages and dynamic languages.
October 6, 2011 08:39 by
ScottLet say you have an XML file and you want to show the information (data in XML file) in GridView. Here, I am going to show you, how to DataBind asp:GridView to the data contained in an XML document.
A standard XML file will look like below:
<?xml version="1.0" encoding="utf-8" ?>
<Fruits>
<Fruit>
<id>1</id>
<name>Apple</name>
<color>Red</color>
</Fruit>
<Fruit>
<id>2</id>
<name>Mango</name>
<color>Yellow</color>
</Fruit>
</Fruits>
The entity in this file is a Fruit. Apparently, there are three columns (sub-nodes of Fruit node) named id, name and color. However, you can’t bind the data defined in this standard XML file directly to the GridView.
First you have to transform the XML data into a format understandable to GridView (e.g. tabular or rows collection format). You can transform a standard XML document into various formats (e.g. HTML markups) by using XSLT. XML document transformation to different XML formats using XSLT demonstrates a basic data transformation for an XML document and contains the transformation template definition for XSLT file.
Once you have applied a valid XML data tranformation, you can use XmlDataSource control to make a connection to your XML file and then bind it to GridView directly. Below is the markup code to bind a GridView to an XmlDataSource.
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="XmlDataSource1">
<Columns>
<asp:BoundField DataField="name" HeaderText="Fruit Name" />
<asp:BoundField DataField="color" HeaderText="Fruit Color" />
</Columns>
</asp:GridView>
<asp:XmlDataSource ID="XmlDataSource1" runat="server" DataFile="~/XMLFile1.xml" TransformFile="~/XSLTFile1.xslt">
</asp:XmlDataSource>
Here, XMLFile1.xml is the actual XML file containg the data you want to bind GridView with and XSLTFile1.xslt is the file containing the desired transformation template.
That's all, I hope you have got an idea of
1. How to bind gridview to xml data
2. How to bind gridview to xml file
3. Binding gridview to xmldocument
4. How to modify XML file in order to make it appropriate for GridView DataSource
September 27, 2011 06:20 by
ScottThis post explains about Shrinking session state in ASP.NET 4.0.
ASP.NET Provides two options for storing session state for web applications.
1. Out of process session state
2. MS SQL server session state
In both the options session-state providers stores the data out side the web application worker process. Session state has to be serialized before it sends it to the external storage.
ASP.NET 4.0 introduces a new compression option for both out-of-process session state providers. We can set the compressionEnabled option in configuration file to true. ASP.NET will compress the session state by using the .NET Framework System.IO.Compression.GZipStream class.
We can configure the session state as follows
<sessionState
mode="SqlServer"
sqlConnectionString="data source=dbserver;Initial Catalog=aspnetstate"
allowCustomSqlDatabase="true"
compressionEnabled="true"
/>
Advantage: With this addition of attribute to web.config file there is substantial reduction in the size of serialized session-state data.