Asp.Net Programming

Tuesday 19 March 2013

How To Use Digital Signature in Asp.net

How To Use Digital Signature in Asp.net

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Collections;
using System.Security.Cryptography;
using System.Security.Permissions;
using System.Security.Cryptography.X509Certificates;
using System.IO;
using System.Text;

public partial class FMS_x509test : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
test();

}
public void test()
{

X509Store store = new X509Store("MY", StoreLocation.CurrentUser);
store.Open(OpenFlags.OpenExistingOnly | OpenFlags.ReadWrite);
//Put certificates from the store into a collection so user can select one.
X509Certificate2Collection fcollection = (X509Certificate2Collection)store.Certificates;
X509Certificate2Collection collection = X509Certificate2UI.SelectFromCollection(fcollection, "Select an X509 Certificate", "Choose a certificate to examine.", X509SelectionFlag.SingleSelection);

X509Certificate2 certificate = collection[0];
// X509Certificate2UI.DisplayCertificate(certificate);
RSACryptoServiceProvider csp = null;
csp = (RSACryptoServiceProvider)certificate.PrivateKey;
// Hash the data
SHA1Managed sha1 = new SHA1Managed();
UnicodeEncoding encoding = new UnicodeEncoding();
byte[] data = encoding.GetBytes("Lokesh");
byte[] hash = sha1.ComputeHash(data);
byte[] signature = csp.SignHash(hash, CryptoConfig.MapNameToOID("SHA1"));

//Verification Code


RSACryptoServiceProvider csp1 = (RSACryptoServiceProvider)certificate.PublicKey.Key;

// Hash the data
SHA1Managed sha11 = new SHA1Managed();
UnicodeEncoding encoding1 = new UnicodeEncoding();
byte[] data1 = encoding.GetBytes("Lokesh");
byte[] hash1 = sha1.ComputeHash(data1);

// Verify the signature with the hash
if (csp1.VerifyHash(hash1, CryptoConfig.MapNameToOID("SHA1"), signature))
{
Response.Write("<script language=javascript> alert('correct');</script/>");
}
else
{
Response.Write("<script language=javascript> alert('No correct');</script/>");
}

// Sign text

// byte[] signature = Sign("Test", "cn=Dashputre Jaideep JYD");
}
}

Wednesday 13 March 2013

Get Current Page Name in Asp.Net

Here I will explain How toGet Current page name in Asp.Net using C# and Vb.Net

C# Code

public static string GetCurrentPageName()
    {
        string sPath = System.Web.HttpContext.Current.Request.Url.AbsolutePath;
        System.IO.FileInfo oInfo = new System.IO.FileInfo(sPath);
        string sRet = oInfo.Name;
        return sRet;
    }

Vb.Net

    Public Shared Function GetCurrentPageName() As String
        Dim sPath As String = System.Web.HttpContext.Current.Request.Url.AbsolutePath
        Dim oInfo As System.IO.FileInfo = New System.IO.FileInfo(sPath)
        Dim sRet As String = oInfo.Name
        Return sRet
    End Function

Check Internet Connection in Asp.net

We can check internet connectivity of system by downloading data of a website from server for that code like as shown below.

<head>

<title>Check Internet Connection Availability using Asp.net</title>

</head>

<body>

<div>

<asp:Button runat="server" ID="btnCheck" Text="Check Internet Connectivity" OnClick="btnCheck_Click"/>

<asp:Label runat="server" ID="lbltxt" />

</div>

</form>

</body>

</html>

C# Code

using System;

using System.Net;

protected void btnCheck_Click(object sender, EventArgs e)

{

WebClient client = new WebClient();

byte[] datasize = null;

try

{

datasize = client.DownloadData("http://www.google.com");

}

catch (Exception ex)

{

}

if (datasize != null && datasize.Length > 0)

lbltxt.Text = "Internet Connection Available.";

else

lbltxt.Text = "Internet Connection Not Available.";

}

Vb.Net

Imports System.Net

Partial Class VBCode

Inherits System.Web.UI.Page

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

End Sub

Protected Sub btnCheck_Click(ByVal sender As Object, ByVal e As EventArgs)

Dim client As New WebClient()

Dim datasize As Byte() = Nothing

Try

datasize = client.DownloadData("http://www.google.com")

Catch ex As Exception

End Try

If datasize IsNot Nothing AndAlso datasize.Length > 0 Then

lbltxt.Text = "Internet Connection Available."

Else

lbltxt.Text = "Internet Connection Not Available."

End If

End Sub

End Class

Tuesday 12 March 2013

Convert String XML to Datatable in C#

Here I will explain how to convert xml string to dataset or xml string to datatable in Asp.Net using C# And Vb.Net

C#

WebClient web = new WebClient();

string url = string.Format("https://api.facebook.com/method/fql.query?query=SELECT url, share_count, like_count, comment_count, total_count, click_count FROM link_stat where url=http://collageprogramming.blogspot.in");

string response = web.DownloadString(url);

DataSet ds = new DataSet();

using (StringReader stringReader = new StringReader(response))

{

ds=new DataSet();

ds.ReadXml(stringReader);

}

DataTable dt = ds.Tables[0];

Vb.Net

Dim web As New WebClient()

Dim url As String = String.Format("https://api.facebook.com/method/fql.query?query=SELECT url, share_count, like_count, comment_count, total_count, click_count FROM link_stat where url=http://collageprogramming.blogspot.in/")

Dim response As String = web.DownloadString(url)

Dim ds As New DataSet()

Using stringReader As New StringReader(response)

ds = New DataSet()

ds.ReadXml(stringReader)

End Using

Dim dt As DataTable = ds.Tables(0)