Monday, August 20, 2012

Debugging is not supported under current trust level settings?

Today When I was debugging a test website I created for learning I got the error “Debugging is not supported under current trust level settings?

This error normally occurs when you keep the website directly under C:\inetpub\wwwroot folder. Anyway that is not a subject here. We will directly go to the simple solution to resolve the issue.

Open your Web.config and add below line in

<system.web>
    <trust level="Full"/> 
    .....
    .....
</system.web>

Monday, August 6, 2012

Window.Confirm in JavaScript.

 

Most of the time during web application development you may get a requirement to redirect the page based on user choice.

Here I am going to show you how to redirect to an another web page or site on click of a JavaScript Ok button.

If you use Window.Confirm in JavaScript you will get OK and Cancel button. So we will redirect to another page only if user click on OK button. If user Click on Cancel button then we will stay on the same page.

So test the code first we will create a simple button

Below is the .ASPX code for creating a button.

<body>
<form id="form1" runat="server">
<div>

</div>
<asp:Button ID="btnSubmit" runat="server" onclick="btnSubmit_Click"
Text="Submit" />
</form>
</body>

Now in Code behind we will write the JavaScript code to redirect to another website.

protected void btnSubmit_Click(object sender, EventArgs e)
{

ScriptManager.RegisterStartupScript(this, this.GetType(), "alertmessage", "javascript:if (window.confirm('You will be redirected to Dotnet Galaxy. Click OK to confirm')) { location.href = 'http://asheej.blogspot.in/'; }", true);

}

Now we will see how the alert will be
Cinfrim box in JavaScript

Monday, July 30, 2012

How to replace carriage return and line feed in a SQL server varchar field

 

I have been facing an issue while importing some data from SQL to CSV file. In one of my SQL fields user entered Enter Key or Line feed, because of that my exported CSV file was not in good format. Rows were broken in between. So I started searching for a solution to replace carriage return and line feed and finally accomplished by writing below query.

SELECT replace ( replace(Col1, char(10),''), char(13), '') as [Column 1] FROM  Test

In the above code "col1" is the column name where you have enter key or line feed and "Test" is the table name.

After using this query I was able to export the data to CSV with proper formatting as I required.

I hope this query may help you also.

Sunday, July 15, 2012

How to validate RadioButton using C#

 

Validating radio button in ASP.NET is not very tough but new programmers always get confused about this and ask the questions in forum for the help. So I thought I will write a simple article related to this topic.

Here I am going to use JavaScript to validate the RadioButton.

First we will create the RadioButton.

<asp:Label ID="Label1" text ="Please select one of your favorite fruits" runat="server"></asp:Label>

<asp:RadioButtonList ID="radiobutton1" runat="server">

<asp:ListItem Text="A.Apples">Apple</asp:ListItem>

<asp:ListItem Text="B.Banana">Banana</asp:ListItem>

<asp:ListItem Text="c.cherry">Orange</asp:ListItem>

<asp:ListItem Text="D.Dates">Grapes</asp:ListItem> </asp:RadioButtonList>

<asp:Button ID="btnSubmit" runat="server" onclick="btnSubmit_Click"

Text="Submit" />

If you look at the above code I have created a RadioButtonList with 4 RadioButtons and a Button.

Now we will write the JavaScript to validate the RadioButtonList

<script type="text/javascript">

function rdValidate()

{

var rd = document.getElementsByName('radiobutton1')



for (var i = 0; i < rd.length; i++)

{

if (rd[i].checked)

{

return true;

}

};

alert("Please select an option");

return false;

}

</script>


Next we will call the JavaScript function to validate the RadioButtonList on Button Click Event.

protected void btnSubmit_Click(object sender, EventArgs e)

{

ClientScript.RegisterStartupScript(GetType(), "Alert", "<script>rdValidate();</script>");

}

That’s it. Now you can run your application and click on the button click event without selecting the RadioButton. You will get the alert message like in below screen print.

Validate Radio Button using JavaScript

Please post your query if you have any in below comment section.

Thanks for reading this article.

Monday, July 2, 2012

Renewed Microsoft MVP Third time a row…

 

I am very happy to inform you all that my MVP status has been renewed third time in row. It’s a very proud moment for me. Thank you all my readers and www.dotnetspider.com members for the support and guidance.

Thursday, May 31, 2012

How to Encrypt and Decrypt web.config using aspnet_regiis

 

Encrypting and decrypting connection string and the web.config is one of the very important task we have to do when we deploy the application in the server. The main reason and the importance of this task is because once you deploy the application with clear text anyone who has permission to access the server can open your web.config and will be able to see the user id and password used to connect to your database.

There are many ways you can encrypt your web.config. Also there are many algorithms available to encrypt your connection string or web.config elements.

Here we will see a very simple method using aspnet_regiis to encrypt and decrypt connectionString element.

First we will have a look at the connectionStrings in web.config

Encrypt Connection String

Below is the command you will be executing to encrypt the connectionStrings.

C:\Windows\Microsoft.NET\Framework\v4.0.30319>aspnet_regiis -pef connectionStrings "C:\Encrypt"

Encrypt Connection String 1

In the above command,  connectionStrings is the element we are encrypting, you may change this if you have appSettings or any other section you wanted to encrypt. Also the path C:\Encrypt is the path where I kept the web.config file. It should be your application path where your web.config exists.

Now we will see after encryption how our connectionStrings looks like by opening our web.config.

Decrypt ConnectionString

You can see that our encrypt command added many keys and the connectionString is completely encrypted which you can not read at all.

Decrypt web.config

Ok, now we will move on to decrypting part of the same connectionStrings. Advantage of this approach is, you don’t need to write any specific code to decrypt the connection string. When you access the connection string form your code behind you will get the connection string in encrypted format.

Below is the command you will be executing to decrypt the ConnectionSteings in case you wanted to read the data in clear text format.

C:\Windows\Microsoft.NET\Framework\v4.0.30319>aspnet_regiis -pdf connectionStrings "C:\Encrypt"

Decrypt ConnectionString 1

Explanation of the above command is same as the one I have given it for encrypting. Now after executing above command you will see the clear text conectionStrings in your web.config.

I hope you are very clear about the idea and concept regarding encrypt and decrypt connectionString. If you still need some more explanation you can read it form MSDN

Sunday, May 27, 2012

How to find row size of the table in MS SQL

 

Some times you may required to know each row size in your table. Today I am going to present you a simple query which is helpful to find the row size of your table in MS SQL.

First we will see the design of the table,

CREATE TABLE [dbo].[Customer](
    [id] [int] NOT NULL,
    [name] [nchar](10) NULL,
    [Address] [nvarchar](50) NULL,
 ) ON [PRIMARY]
 
GO

Now we will insert some values to the table

INSERT INTO [Customer]([id] ,[name] ,[Address]) VALUES (1 ,'John','Spain')
INSERT INTO [Customer]([id] ,[name] ,[Address]) VALUES (1 ,'James','Wales')
INSERT INTO [Customer]([id] ,[name] ,[Address]) VALUES (1 ,'Michael','Scotland')
INSERT INTO [Customer]([id] ,[name] ,[Address]) VALUES (1 ,'Mark','United Kingdom')
GO

Now we will see the query to get the row size,

select
row_number() over (order by id desc) as [ROW],
ISNULL(datalength(id),0)+
ISNULL(datalength(name),0)+
ISNULL(datalength(Address),0) as RowSize
from Customer

Output of the above query will be

ROW    RowSize
1    52
2    40
3    34
4    34

Cheers!

Thursday, May 3, 2012

How to find application path in Console/VB.NET windows application

In ASP.NET web application we normally use Server.MapPath to get the application root folder path. But what we will write in VB.NET windows and console application???

Here is the two lines of code which will help you to get the application path in VB.NET windows and console application.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
 
namespace ConsoleApplication2
{
    class TestConsole 
    {
        static void Main(string[] args)
        {
            string strLocation = System.AppDomain.CurrentDomain.BaseDirectory;
            Console.WriteLine(strLocation);
        }
    }
}

Below is the screen print of the above code with output,

Application path in Console application

Wednesday, May 2, 2012

Open MS Word document in web browser

 

This is one of the common request you will get when you do any file operation in your project. This code can be used to open EXCEL, Power Point, PDF etc.

protected void btnWord_Click(object sender, EventArgs e)
{
    string strWordFile = @"c:/Test.docx";
    FileInfo objDoc = new FileInfo(strWordFile);
    Response.Clear();
    Response.ContentType = "Application/msword";
    Response.AddHeader("content-disposition", "attachment;filename=" + objDoc.Name);
    Response.AddHeader("Content-Length", objDoc.Length.ToString());
    Response.ContentType = "application/octet-stream";
    Response.TransmitFile(objDoc.FullName); 
    Response.End(); 
}

Tuesday, May 1, 2012

How to add different column values as Tooltip for DropDownList in ASP.NET

 

Sometimes we may have to show different field from the database as tool tip for the DropDownList in ASP.NET.

Below is a sample code to display the tooltip for DropDownList. Here I have used different field from the database to show as tooltip.

protected void btnLoad_Click(object sender, EventArgs e)
        {
            string strCon = System.Configuration.ConfigurationManager.ConnectionStrings["sqlConnection"].ToString();
 
            SqlConnection conn = new SqlConnection(strCon);
            conn.Open();
            SqlDataAdapter da = null;
            DataSet dsCountry = new DataSet();
            try
            {
                string strCountrySQL = "select id, name, Address from dbo.Customer";
                da = new SqlDataAdapter(strCountrySQL, conn);
                da.Fill(dsCountry);
                DropDownList1.DataSource = dsCountry;
                DropDownList1.DataTextField = "name";
                DropDownList1.DataValueField = "id";
                DropDownList1.DataBind();
 
                int ItemCount = DropDownList1.Items.Count;
                for (int i = 0; i < ItemCount; i++)
                {
                    DropDownList1.Items[i].Attributes.Add("Title", dsCountry.Tables[0].Rows[i]["Address"].ToString());
                }
                DropDownList1.Items.Insert(0, new ListItem("--Select--", "--Select--"));
                DropDownList1.SelectedItem.Selected = false;
                DropDownList1.Items.FindByText("--Select--").Selected = true;
            }
            catch (Exception ex)
            {
                lblMsg.Text = "Error!! <br>+" + ex.Message.ToString();
            }
            finally
            {
                dsCountry.Dispose();
                da.Dispose();
                conn.Close();
                conn.Dispose();
            }

Below is the screen print of the tooltip,

ToolTip

Friday, April 20, 2012

How to use IN Clause with parameter in MS SQL

 

You might be wondering how to pass the value as parameter in IN clause. It is a kind of tricky one. If you directly execute your select query by passing the parameter your query will through error.

Here we will see how it can be done,

First we will create the table

CREATE TABLE [dbo].[EMP](
    [ID] [int] NULL,
    [Name] [nchar](10) NULL
) ON [PRIMARY]
 
GO

Now we will insert some values to the table

INSERT INTO [Test].[dbo].[T] ([ID],[Name]) VALUES(1,'Mike')
INSERT INTO [Test].[dbo].[EMP] ([ID],[Name]) VALUES(2,'John')
INSERT INTO [Test].[dbo].[EMP] ([ID],[Name]) VALUES(3,'Russel')
INSERT INTO [Test].[dbo].[EMP] ([ID],[Name]) VALUES(4,'Thomas')
INSERT INTO [Test].[dbo].[EMP] ([ID],[Name]) VALUES(5,'David')
GO

Finally we will query the table using IN. I want all the Employee with the ID in 3,4,5 and our query for that should be

select * from t
 
Declare @id varchar(20)
set @id= '3,4,5'
exec('SELECT * FROM EMP WHERE ID IN('+@id+')')
 

Above query was useful if you wanted to use INT or any other numeric data type in your IN clause. What you will do if you wanted to use it for char data type?

Yes we will see that as well here.

Query for Char data type should be,

DECLARE @id VARCHAR(MAX)
set @id= 'Mike,John,David'
SELECT @id = '''' + REPLACE(@id,',',''',''') + ''''
EXEC('SELECT * FROM EMP WHERE Name IN('+@id+')')
GO

Result after executing above query for Int data type,

Query

Result after executing above query for CHAR data type,

Query1

Wednesday, April 11, 2012

How to call Stored Procedure from Trigger in MS SQL

 

Another interesting Interview question “Can we call Stored procedure form Trigger in MS SQL”? What will be your answer YES or NO? Answer should always be “YES”.

You can call Stored Procedure from trigger. In this article we will go through a simple After Insert trigger as an example.

create trigger trg_Ins_CustTrigger on Customer
After Insert 
AS
Declare @Name as varchar(100)
Declare @Address as varchar(100)
select @Name=Name, @Address=Address from inserted
exec CustDet @Name, @Address
 

I believe above code is self explanatory as the table and field names I have used is a clear English text.

If you have any question please post it in comment section.

Tuesday, April 3, 2012

How to make Marquee in ASP.NET web page and dynamically assign the value to it.

 

When you make a web application it is always good to make a colourful user interface.  One of the most attractive feature in HTML is Marquee. Today we will see how to use marquee in ASP.NET web application.

Here we will use label to assign the text which moves inside the marquee tag.

We will see the code now,

<div> 
<marquee direction="right" scrollamount="2" loop="true" width="100%" bgcolor="#ffffff" >
    <asp:Label id="lblMarquee" runat="server" ForeColor="ForestGreen" Font-Bold="True" ></asp:Label>
</marquee>
</div>

Here what we are doing is we kept the label inside marquee tag so label will move based on the marquee settings.

Now if you assign any value from your code behind to this label it will move or rotate based on the marquee settings.

Wednesday, March 28, 2012

Microsoft open sourcing ASP.NET MVC 4, ASP.NET Web API, ASP.NET Web Pages v2 (Razor) - under the Apache 2.0 license.

 

Microsoft announce that developers outside the Microsoft can now submit code snippet and patches which they may review and include in the products.

You can find more details on Scott Guthrie's blog

“We will also for the first time allow developers outside of Microsoft to submit patches and code contributions that the Microsoft development team will review for potential inclusion in the products,” Guthrie says. “We announced a similar open development approach with the Windows Azure SDK last December, and have found it to be a great way to build an even tighter feedback loop with developers – and ultimately deliver even better products as a result.”

Also you can find the source on CodePlex.

Tuesday, March 27, 2012

Query to find number of users connected in an MS SQL database

 

Sometimes you may get an error from your application saying "Connection pool size exceeded".

Here I am going to explain you few queries which can be used to find out the number of open connections in your MS SQL database and also the query to find the maximum connections allowed in SQL server.

First we will check, what is the maximum connections SQL server will allow you to connect.

SELECT @@MAX_CONNECTIONS AS 'Maximum Connections Allowed in the database'

Now you know that how many connections you can have in your database. So we will check how many are already used.

Below query can be used to find the number of connections in each database in your server if you execute this query against master database.

SELECT DB_NAME(dbid) as [Database Name], COUNT(dbid) as [Number of Connections] from master.dbo.sysprocesses with (nolock)
WHERE dbid > 0 GROUP BY dbid

Now we will see who all are the users connected to your database.

Below query will show you the login name and the host name of the user connected to your database. In below query you may change the database name when you execute in your system.

SELECT LOGINAME=RTRIM(LOGINAME),HOSTNAME FROM MASTER.DBO.SYSPROCESSES
WHERE DB_NAME(DBID) = 'DataBaseName' AND DBID != 0


Now at the end we will see a very simple query which can be used to show all the sessions that are currently established in the database.

sp_who2