Home: November 2021

Tuesday, November 30, 2021

Response.redirect like in javascript insimple html

// Simulate a mouse click:

window.location.href = "http://www.w3schools.com";

// Simulate an HTTP redirect:
window.location.replace("http://www.w3schools.com");

reference= https://www.w3schools.com/howto/howto_js_redirect_webpage.asp

Jquery bootstrap collapse toggle

https://www.w3schools.com/bootstrap/tryit.asp?filename=trybs_ref_js_collapse&stacked=h

difference between Varchar and nvarchar and char

Varchar:-

It is a variable that has a length data type.
It is use to store non-Unicode characters.
It Occupy 1 byte of space for each character.

Nvarchar:-

It is a variable that has length data type.
It is use to store Unicode characters.
It Occupy 2 bytes of space for each character.

Char:-

It is a fixed length data type
Used to store non-Unicode characters
Occupiers 1 byte of space for each character

Drop down list asp.net C# from database

ddlPositions.SelectedValue = dt.Rows[0]["PostHeld"].ToString();

ddlTypeOfCourt.SelectedValue= courtApplicationDatesDTO.CourtTypeId.ToString();

selectedvalue will work

selecteditem.value will not work on above

but when we set the value to object from drop down selecteditem.value will work as below

courtApplicationDatesDTO.CourtTypeId = Convert.ToInt32(ddlTypeOfCourt.SelectedItem.Value);

https://www.c-sharpcorner.com/UploadFile/0c1bb2/fill-Asp-Net-dropdown-list-from-database-table-using-Asp-Net/

https://www.aspsnippets.com/Articles/Bind-Populate-ASPNet-DropDownList-using-DataTable-DataSet-in-C-and-VBNet.aspx

Grid edit and update facility in asp.net C#

https://www.c-sharpcorner.com/UploadFile/1e050f/edit-and-update-record-in-gridview-in-Asp-Net/

<asp:GridView ID="grd_Batch" AutoGenerateColumns="false" runat="server" DataKeyNames="Batch_id"

AllowPaging="true" PageSize="20" PagerSettings-Position="Bottom" PagerSettings-PageButtonCount="10"

Width="100%" CssClass="table table-bordered table-hover table-stripped table-condensed table-responsive"

OnRowEditing="grd_Batch_RowEditing" OnRowCancelingEdit="grd_Batch_RowCancelingEdit" OnRowDataBound="grd_Batch_RowDataBound"

OnRowUpdating="grd_Batch_RowUpdating" OnRowDeleting="grd_Batch_RowDeleting" OnRowCommand="grd_Batch_RowCommand">

<asp:TemplateField HeaderText="EDIT">

wati.io chatbot for whatsapp documentation

https://docs.wati.io/reference/post_-serverurl-api-v1-updatecontactattributes-whatsappnumber

Saturday, November 27, 2021

An introduction to Jquery.

Jquery is a javascript library. Simple syntax of Jquery.

----------------------------**************----------------------------

<!DOCTYPE html>

<html>

<head>

$(document).ready(function(){

$("p").click(function(){

$(this).hide();

});

</script>

</head>

<body>

<p>If you click on me, I will disappear.</p>

<p>Click me away!</p>

<p>Click me too!</p>

</body>

</html>

An introduction to node.js.

Node.js is an open source server environment
Node.js is free
Node.js runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.)
Node.js uses JavaScript on the server

Node.js uses asynchronous programming!

And download node.js from https://nodejs.org/en/

reference:- https://www.w3schools.com/nodejs/default.asp

How to download mongodb database. An intro to mongodb database

MongoDB is not a SQL database, it is a document database.

Download Mongodb compass (The GUI for MongoDB)

https://www.mongodb.com/try/download/compass

Also you have to download mongodb community.

https://www.mongodb.com/try/download/community

-------------------****************---------------------

Also you can use MongoDB Atlas for cloud database.

---------------------***************-----------------------

In mangodb, you can say, collections are your tables.

And documents are your data(records)

-----------------------

To find the data in filter(in mongodb compass), enter below code

{ Country: "Brazil" }

and click on find.

------------------------------***********************---------------------------

Mongodb tutorials :- https://docs.mongodb.com/compass/current/query/filter/

Creating Login logic for asp.net C# and Stored procedure for finding Login and password

Create procedure [dbo].[spLogin]
(
@Email nvarchar(50),
@Password nvarchar(50)
)
as
begin
Select COUNT(*) from UserRegistration where Email=@Email and Password=@Password
end
---------------------------------
Clicking on Login button
protected void btnLogin_Click(object sender, EventArgs e)
{
string CS = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;
using (SqlConnection con=new SqlConnection(CS))
{
SqlCommand cmd = new SqlCommand("spLogin", con);
cmd.CommandType = CommandType.StoredProcedure;
con.Open();
cmd.Parameters.AddWithValue("@Email",txtEmail.Text.Trim());
cmd.Parameters.AddWithValue("@Password", Decrypt(txtPassword.Text.Trim()));
int Username = (Int32)cmd.ExecuteScalar();
if (Username == 1)
{
Session["Username"] = txtEmail.Text;
Response.Redirect("Welcome.aspx");
Session.RemoveAll();
}
else
{
lblMessage.ForeColor = System.Drawing.Color.Red;
lblMessage.Text = "Invalid username and password";
}
}
}
reference:- https://www.c-sharpcorner.com/blogs/how-to-login-with-encrypted-password-in-asp-net
https://www.c-sharpcorner.com/blogs/how-to-create-user-registration-form-with-encrypted-password-using-asp-net#ReadAndPostComment

Session time in asp.net

If you want to set the timeout to 20 minutes, use something like this:

    <configuration>
      <system.web>
         <sessionState timeout="20"></sessionState>
      </system.web>
    </configuration>

reference:-  https://stackoverflow.com/questions/1205828/how-to-set-session-timeout-in-web-config

https://www.c-sharpcorner.com/blogs/how-to-set-session-timeout-in-asp-net1

Change the website white background to black in google chrome dark mode - Chrome black extension

There are two options:-

1)You can change by using

chrome://flags/#enable-force-dark

>Click on enable(select "enabled with simple cielab based inversion") or (select "enable with selective inversion of everything") and than click on Relaunch.(Screenshot below)

or the best option you can select that I have tested (enabled the selective inversion of non-image elements)

----------------------------------*********************-----------------------------------

2) You can click on Customize Chrome (screenshot below)

>Than click on Colors and themes.(screenshot below)

>Select the color and Click on done.

Extensions are for chrome

https://chrome.google.com/webstore/detail/dark-reader/eimadpbcbfnmbkopoojfekhnkhdbieeh

https://darkreader.org/

Friday, November 26, 2021

server.mappath in asp.net

Server.MapPath(".")¹ returns the current physical directory of the file (e.g. aspx) being executed
Server.MapPath("..") returns the parent directory
Server.MapPath("~") returns the physical path to the root of the application
Server.MapPath("/") returns the physical path to the root of the domain name (is not necessarily the same as the root of the application)

reference:- https://stackoverflow.com/questions/275781/server-mappath-server-mappath-server-mappath-server-mappath

Encryption and decryption of password in asp.net

//For decryption of password

-----------------------------***************************------------------------------

private string Decrypt(string clearText)
{
string EncryptionKey = "ABCDEFGHIJKLMNOPQRSTUVWXYZ123456789";
byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
using (Aes encryptor = Aes.Create())
{
Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
encryptor.Key = pdb.GetBytes(32);
encryptor.IV = pdb.GetBytes(16);
using (MemoryStream ms = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(clearBytes, 0, clearBytes.Length);
cs.Close();
}
clearText = Convert.ToBase64String(ms.ToArray());
}
}
return clearText;
}

------------------------********************--------------------

For encryption of password

private string Encrypt(string clearText)
{
string EncryptionKey = "ABCDEFGHIJKLMNOPQRSTUVWXYZ123456789";
byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
using (Aes encryptor = Aes.Create())
{
Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
encryptor.Key = pdb.GetBytes(32);
encryptor.IV = pdb.GetBytes(16);
using (MemoryStream ms = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(clearBytes, 0, clearBytes.Length);
cs.Close();
}
clearText = Convert.ToBase64String(ms.ToArray());
}
}
return clearText;
}