Instructions: 

1. Using UserHostAddress property 
   Request.UserHostAddress   gives you the IP address of client visiting your website.
2. Using ServerVariables
   Request.ServerVariables["REMOTE_ADDR"]   gives you the IP address of client’s machine as well. Use any of these two methods to get Client’s IP Address.

Instructions:

1. If you are sure, you don’t want to use session on any of your website page, then turn off sessions completely by adding following lines of code in your Web.Config file under <System.Web> section.
   
   

   <sessionState mode="Off"></sessionState>

   

2. If you want to use session state on some pages, not the entire website, then you can disable session state for your entire website and then you can enable it for those particular pages. Use then following line of code to disable session state for all of the pages.
   
   

   <pages enableSessionState="false">

   
   after this you can enable session state for a particular page by enabling this in the page directive of particular page using the following syntax.
   
   

   <%@ Page Language="C#" EnableSessionState="True"...

   

There are number of pre defined object which we can create in web.config. But the main point of this article is, storing some object of custom type in web.config. This can be very useful in a number of scenarios.

Instructions:

1. First of all we have to create our own custom object in appSettings section of web.config which we will refer to in our web forms.
   
   

   <appSettings>
  <add key="HowToIdeas" value="This is a simple message.." />
</appSettings>

2. To read its value in code file, add the following namespaces in your code file.
   
   

   using System.Configuration;
using System.Web.Configuration;

3. Now use the following line of code to retrieve the value of the object we have created.
   
   

   String s = ConfigurationManager.AppSettings["HowToIdeas"].ToString();
Response.Write(s);

4. Response.Write will write the string on our web page. Here is the output of these statements in my web page.
   
5. Now to change the value of this object, use the following statement.
   
   

       Configuration config = WebConfigurationManager.OpenWebConfiguration(Request.ApplicationPath);
    config.AppSettings.Settings["HowToIdeas"].Value = "This is the updated message..";
    config.Save();

6. So when this will run, it will change the value of our object in web.config. But this change will be reflected back the next time when the page will be reloaded. Actually this statement will change the actual value in web.config which will be saved after the page gets fully loaded and this value will be retrieved only after that.
7. On my page when I click the second button (Original Message) the following output will be shown.
   
8. After that when I click the 1st button (change value), I get the following output.
   
9. In above screenshot the message shown on page is same as the previous one, but actually the value is changed and will be reflected back the next time. So when I click the third button (New Value), I get the following output.
   
10. And when you stop the website, you will also get a message stating your web.config file has been updated from outside.
    
11. Here is the snapshot of the whole code I am running on this page.
    

Instructions:

1. Before editing data in DataSet, you need to have data in a DataSet instance. Using following code, I fetched all the data from [abc] Table into DataSet instance ds.
   
   

   SqlConnection con = new SqlConnection();
con.ConnectionString = @"Provide your own connection string here";
SqlCommand cmd = new SqlCommand();
cmd.CommandText = "select * from [abc]";
cmd.Connection = con;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);

   and here is the output in browser, If I bind this DataSet to any Data Binding control(Repeater used here)
   

2. In the above image, I want to change the value for Address column ( [Eadd] – column name or 2 index) in 2nd row ( i.e index 1), then I can do so using any the following code.
   
   

   ds.Tables[0].Rows[1]["Eadd"] = "New Value"; //Eadd is the actual column name of Address column in Database

   or
   
   

   ds.Tables[0].Rows[1][2] = "New Value";

3. Here is the output in Browser after using any of the above statement for editing data in DataSet.
   

Instructions:

1. As SqlDataAdapter is a disconnected approach to read data, so we just need to have the connection string of our SQL Server connection, we don’t need to open connection to SQL Server.
   
   

   SqlConnection con = new SqlConnection();
con.ConnectionString = @"Provide your own connection string here";

2. After creating connection to your Database, you will need to build the Query or Command to fetch the data from any Table of that Database using SqlCommand class. Also you have to mention this that on which connection that command will be executed.
   

   SqlCommand cmd = new SqlCommand();
cmd.CommandText = "select * from [abc]";
cmd.Connection = con;

3. Now this command will select all the rows and columns of the Table [abc] present in my Database. Currently I have 3 columns [Eid], [Ename], [Eadd] in this Table.
4. Now using this command we will store a reference to all the data of the Table in SqlDataAdapter class instance using the following statement.
   

   SqlDataAdapter da = new SqlDataAdapter(cmd);

5. Now we have to fill the data in DataSet, so our DataSet instance will fetch all the data and store in itself. So after that, we don’t need an active connection to SQL Server to read data as all the data will be present in DataSet.
   
   

   DataSet ds = new DataSet();
da.Fill(ds);

6. Now, this DataSet instance ds has the reference to all the records of the Table. So just Bind this instance to our Repeater control to show all the data in that.
   

   Repeater1.DataSource = ds;
Repeater1.DataBind();

7. Now we are done with the code, all we have to do now is create template for our Repeater control, so that the data we have bound to that will get shown in the way we want. I have used the same template which I had used in my previous article on Data Binding to Repeater control over here.
   

   <asp:Repeater ID="Repeater1" runat="server">
    <ItemTemplate>
        <table width="50%">
            <tr>
                <td width="33%" align="left">
                    <b>ID:</b><%#Eval("Eid")%></td>
                <td width="33%" align="left">
                    <b>Name:</b><%#Eval("Ename")%></td>
                <td width="33%" align="left">
                    <b>Address:</b><%#Eval("Eadd")%></td>
            </tr>
        </table>
    </ItemTemplate>
    <SeparatorTemplate>
        <hr /><hr />
    </SeparatorTemplate>
</asp:Repeater>

8. Here is the output in Browser.
   
   

   You can download my sample code as well. Click here To Download.
   Note: This method is executed in Default3.aspx page of the sample website which you can download from the link given in above line.

Instructions:

1. First of all you will need to create and open connection to your Database in SQL Server using Connection String. If you don’t know how to do this, you can view my article on How To Create SQL Connection.
2. After creating and opening connection to your Database, you will need to build the Query or Command to fetch the data from any Table of that Database using SqlCommand class. Also you have to mention this that on which connection that command will be executed.
   
   

   SqlCommand cmd = new SqlCommand();
cmd.CommandText = "select * from [abc]";
cmd.Connection = con;

3. Now this command will select all the rows and columns of the Table [abc] present in my Database. Currently I have 3 columns [Eid], [Ename], [Eadd] in this Table.
4. Now using this command we will store a reference to all the data of the Table in SqlDataReader class instance using the following statement.
   
   

   SqlDataReader rd = cmd.ExecuteReader();

5. Now, this SqlDataReader instance rd has the reference to all the records of the Table. So just Bind this instance to our Repeater control to show all the data in that.
   
   

   Repeater1.DataSource = rd;
Repeater1.DataBind();

6. Now we are done with the code, all we have to do now is create template for our Repeater control, so that the data we have bound to that will get shown in the way we want. I have used the same template which I had used in my previous article on Data Binding to Repeater control over here.
   
   

   <asp:Repeater ID="Repeater1" runat="server">
    <ItemTemplate>
        <table width="50%">
            <tr>
                <td width="33%" align="left">
                    <b>ID:</b><%#Eval("Eid")%></td>
                <td width="33%" align="left">
                    <b>Name:</b><%#Eval("Ename")%></td>
                <td width="33%" align="left">
                    <b>Address:</b><%#Eval("Eadd")%></td>
            </tr>
        </table>
    </ItemTemplate>
    <SeparatorTemplate>
        <hr /><hr />
    </SeparatorTemplate>
</asp:Repeater>

7. Here is the output in Browser.
   

You can download my sample code as well. Click here To Download.
Note: This method is executed in Default2.aspx page of the sample website which you can download from the link given in above line.

• link repeater to sqldatareader (1)

To create Typed Dataset, first see my article on How To Create Typed Dataset In Visual Studio

Instructions:

1. Create a new instance of that dataset in code.
   
   

   myDataset ds = new myDataset();

2. Now you have to bind data to this Dataset. For this, use SqlDataAdapter class to select all the data of the same Table, and fill this dataset.
   
   

   SqlConnection con = new SqlConnection();
con.ConnectionString = @"Data Source=HOWTOIDEAS;Initial Catalog=HowToIdeas;User ID=RohitGarg;Password=sqlserver";
if (con.State == System.Data.ConnectionState.Closed)
    con.Open();
SqlCommand cmd = new SqlCommand();
cmd.CommandText = "select * from [abc]";
cmd.Connection = con;
SqlDataAdapter da = new SqlDataAdapter(cmd);
myDataset ds = new myDataset();       
da.Fill(ds, ds.Tables[0].TableName);

3. Once you fill the Dataset, you are ready to use this any way you like.
4. You can bind this Dataset to any Data Binding control, by providing this Dataset as DataSource for that Data Binding control. Here is an example of binding the data in Repeater control
   
   

   Repeater1.DataSource = ds;
Repeater1.DataBind();

   

5. To edit a particular column value of particular row, try the following code.
   
   

   ds.abc[2].Eadd = "My Address";

6. In upper line of code, 2 is the index of the row whose Eadd column’s value we want to edit. Here is the output in browser
   
7. If you want to fetch value of any column, you can do so by using following code
   
   

   string s = ds.abc[1].Ename;
Response.Write("Fetched Value Is : " + s);

8. In upper line, I have fetched the Ename column value of the row having index 1 or 2nd row. and then I have printed the fetched value on the page using Response.Write function.
   

• how to use dataset in asp net (12)

Instructions:

1. Open Visual Studio and create a website or open any existing one.
2. Open Solution Explorer and then right click on your Website and select Add New Item.
   
3. In the Add New Item dialogue, Select Dataset and give it any name you like and click Add.
   
4. If Visual Studio prompts you to add this Dataset in App_Code folder, just click Yes to continue.
   
5. After this Visual Studio will open Dataset Designer for your Newly created Dataset. Now what you have to do is, drag and drop table, views, etc. from Server Explorer to this designer and Visual Studio will do all the work to bind those tables to your Dataset.
6. So, to add Tables, open Solution Explorer and then explore your Database there, select the Table you want to add and then drag and drop that Table to Dataset Designer
   
7. After this Visual Studio will show you the Table Columns and a Bind_Data function to fill the Dataset in the Designer.
   
8. If you want to remove or add any column to this, you can do so this as well. Right click on your Table in the Dataset Designer and the select Add->Column. There are some other options as well to select and configure your Dataset table. You can also delete Table here.
   
   
   

Now To Use this Dataset in Code, You can see my Article On How To Use Typed Dataset In Code

• Repeater control doesn’t have any User Interface to define layout of the control. Like in GridView, DataList, etc., you can open task list and then can choose default template for that control. In Repeater control, you have to describe in HTML only, that how your data should be represented to user when data binding occurs.
• This control doesn’t have built in support for Paging like GridView has. DataList too don’t have built in support for Paging. But for both we can enable Paging by some other methods that are beyond the scope of this article, and I will try to cover them soon.
• This Control displays data in a single column. Now here what Single Column means is, this control can’t create columns on its own, but if we want to create columns, we have to define a table inside this control which will be available in the only column this control have, but that table on its own can have multiple columns to display data categorized. In the following example, I will show you how to do this thing. DataList have built in support for dividing data in columns, and controls like GridView too have some advanced features based on these concepts.

Now before starting, I want to write about what I will be doing in the following example. In following example, I will be using a class Employees with properties like Employee ID, Employee Name, Employee Address. In the Page Load event, I will be creating a List of this Employees class, and will add some Employee’s information to that list. and then I will bind that data to Repeater and in Repeater I will show this data in columns, first column for Employee ID, 2nd for Employee name, 3rd for Employee Address. And also I will add two horizontal lines between two records two separate them for clear view.

Instructions:

1. Start by creating a Class for your Webpage. For example purpose, I have created an Employee class with three private Fields (eid – Int32, ename – string, eadd – string), three public properties with get element to return the value stored in those private fields (Eid – Int32, Ename – string, Eadd – string). Then i have created a constructor with three parameters one for every field of the class, and then assign the value passed by user to the fields. You can download my sample project at the bottom of this page, which contains that Class as well.
2. Now in the Page_Load event, I have created a List of this Employee class and added four record in that list. After that, I bind that List to the Repeater Control as follows
   
   

   List<Employees> employees = new List<Employees>();
employees.Add(new Employees(1, "Rohit", "abcd"));
employees.Add(new Employees(2, "Ankur", "bcde"));
employees.Add(new Employees(3, "Navneet", "cdef"));
employees.Add(new Employees(4, "Vipul", "defg"));
Repeater1.DataSource = employees;
Repeater1.DataBind();

3. Now in the Source View of the Page, I modified the Item Template to bind the data in the way I want. In Item Template for this Repeater Control, I have created a table with 50% width of the user screen and then in that table, I created a new row which contains three data cells, one for every property of the Employee class.
4. You can write simple HTML text the way you want, which will be shown as it is in the browser, but where you want to show data from the data source, you have provided, you have to Evaluate the value of the key whose data you want to display there. Say, if in a column you want to display the data of property Eid, you have to bind it there as follows
   
   

   <%#Eval(“Eid”)%>

   Now using this you will be able to bind data to your Repeater Control the way you want, but obviously you need to have some good knowledge of HTML as well.

5. After that I have created SeparateTemplate for the Repeater Control and just added two horizontal lines to display information in readable form. As this template will be called after every ItemTemplate binding.
6. Here is my HTML code for the Repeater Control
   
   

   <asp:Repeater ID="Repeater1" runat="server">
            <ItemTemplate>
                <table width="50%">
                    <tr>
                        <td width="33%" align="left">
                            <b>ID:</b><%#Eval("Eid")%></td>
                        <td width="33%" align="left">
                            <b>Name:</b><%#Eval("Ename")%></td>
                        <td width="33%" align="left">
                            <b>Address:</b><%#Eval("Eadd")%></td>
                    </tr>
                </table>
            </ItemTemplate>
            <SeparatorTemplate>
                <hr /><hr />
            </SeparatorTemplate>
        </asp:Repeater>

7. Here is the snapshot of output in browser
   

You can download my sample code. Click Here To Download Sample Code.

Instructions:

1. If you want to Clear all the Session variables you have created, you can use any of the following command.
   
   

   Session.Clear();

   or
   
   

   Session.RemoveAll();

2. Upper lines of code will clear all the Session variables but Session is still open for the user. So, if any time you want to close the Session for a user, you have to abandon it by using following command.
   
   

   Session.Abandon();

3. If you want to remove a particular variable from Session not all, then you have to use Remove method of Session class.
   
   

   Session.Remove(“variable_name”);