export to excel in grid - simplest way

   Response.Clear();

        Response.Buffer = true;

        Response.ClearContent();

        Response.ClearHeaders();

        Response.Charset = "";

        string FileName = "Vithal" + DateTime.Now + ".xls";

        StringWriter strwritter = new StringWriter();

        HtmlTextWriter htmltextwrtter = new HtmlTextWriter(strwritter);

        Response.Cache.SetCacheability(HttpCacheability.NoCache);

        Response.ContentType = "application/vnd.ms-excel";

        Response.AddHeader("Content-Disposition", "attachment;filename=" + FileName);

        GridView1.GridLines = GridLines.Both;

        GridView1.HeaderStyle.Font.Bold = true;

        GridView1.RenderControl(htmltextwrtter);

        Response.Write(strwritter.ToString());

        Response.End();

RDLC Report manual export to pdf, image etc - report viewer export to pdf manually

 https://www.c-sharpcorner.com/blogs/rdlc-report-export-on-server

https://www.aspsnippets.com/Articles/2568/Export-RDLC-Report-to-PDF-without-using-ReportViewer-in-ASPNet-with-C-and-VBNet/

How to add dummy data to datatable with multiple columns

 DataTable dt = new DataTable("DummyData");

        dt.Columns.Add("Id", typeof(int));

        dt.Columns.Add("Name", typeof(string));

        dt.Columns.Add("City", typeof(string));

        DataTable dt1 = new DataTable("DummyData");

        dt1.Columns.AddRange(new DataColumn[] {

        new DataColumn("Id", typeof(int)),

        new DataColumn("Name", typeof(string)),

        new DataColumn("City", typeof(string))

    });

        dt.Rows.Add(1, "John Doe", "New York");

        dt.Rows.Add(2, "Jane Smith", "London");

        dt.Rows.Add(3, "Peter Jones", "Paris");

//or

 //  DataRow newRow = dt.NewRow();

    newRow["Id"] = 4;

   // newRow["Name"] = "Alice Brown";

    //newRow["City"] = "Tokyo";

    //dt.Rows.Add(newRow);

        GridView1.DataSource = dt;

        GridView1.DataBind();

How to add dummy data to datatable or gridview with array of string

   string[] myString1 = { "sum", "minus"};

        

        DataTable dt = new DataTable();

        dt.Columns.Add("Name", typeof(string));

        foreach (string item in myString1)

        {

            System.Data.DataRow row = dt.NewRow();

            row["Name"] = item; // Assign the string to the column

            dt.Rows.Add(row); // Add the row to the DataTable

        }

        

        GridView1.DataSource = dt;

        GridView1.DataBind();

How to open binary file from database on browser- only display

 byte[] bytes =   file.FileData;

Response.Clear();

    Response.ContentType = file.ContentType;

Response.BinaryWrite(bytes);

https://www.aspsnippets.com/questions/206135/Open-Show-Base64-PDF-data-in-new-window-Tab-using-C-and-VBNet-in-ASPNet/

How to view the image in browser from database - binary image from database - asp.net

  string alert1 = "var image = new Image();";

        alert1+= "image.src='data:image/jpg;base64,"+ Convert.ToBase64String(bytes)+"';";

        alert1 += "var w = window.open('');";

              alert1+= "w.document.write(image.outerHTML);";

           ScriptManager.RegisterStartupScript(this, this.GetType(), "OpenNewTabScript", alert1, true);

ref:-https://stackoverflow.com/questions/27798126/how-to-open-the-newly-created-image-in-a-new-tab

How to display binary images from database - How to view images from database - view binary images - asp.net c# - How to download file from database

protected void FetchImage(object sender, EventArgs e)

{

    string id = ddlImages.SelectedItem.Value;

    Image1.Visible = id != "0";

    if (id != "0")

    {

        byte[] bytes = (byte[])GetData("SELECT Data FROM tblFiles WHERE Id =" + id).Rows[0]["Data"];

        string base64String = Convert.ToBase64String(bytes, 0, bytes.Length);

        Image1.ImageUrl = "data:image/png;base64," + base64String;

    }

}

ref:- https://www.aspsnippets.com/Articles/660/Display-image-from-database-in-Image-control-without-using-Generic-Handler-in-ASPNet/ 

How to download file using binarywrite function and download file from url link - using webclient function

  protected void btnClickMe_Click(object sender, EventArgs e)

    {

                WebClient client = new WebClient();

        byte[] bytes = client.DownloadData("https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgahqj6mU5OTtB-PLGl36tvYYv02OuXuR__pTakG-Y8dBc36TZaSboLga6RwM8DJUQKAwJ_sSjkp-4nhW1udweEejazbrZ50z2cb1ynJgIaZNBlrSIy827bc_5iY6UesB4/s220/WIN_20220808_12_53_18_Pro.jpg");

        Response.Clear(); //This must be add ,without this the file that you save will not be open

        Response.AddHeader("content-disposition", "attachment; filename=1.jpg"); 

         

 //Response.ContentType = System.Net.Mime.MediaTypeNames.Image.Jpeg; 

        //"application/octet-stream"; 

        Response.BinaryWrite(bytes);

        Response.Flush();

        Response.End();

    }

Note:-         Response.Clear(); //This must be add ,without this the file that you save will not be open

How to convert div to pdf using itextsharp asp.net - C# - Simplest and less code

First you have to download itextsharp.dll and itextsharp.pdfa.dll files and  you have to give the font size as below because in some case it will give error that font size is small.

 <form id="form1" runat="server">

        <asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>

    <div id="mainDiv" runat="server">

        

        <asp:Label runat="server" Text="Test" Font-Bold="true" Font-Size="13px" />

        <br />

        <asp:Label runat="server" Text="E-Admit Card" Font-Bold="true" Font-Size="13px" />

        <br />

        <table border="1">

            <tr>

                <td>

                    <asp:Label runat="server" Text="Date Of Test:" Font-Size="13px" />

                </td>

                <td>

                    <asp:Label runat="server" Text="20/11/2024" Font-Size="13px" />

                </td>

            </tr>

        </table>

        

    </div>

        <asp:Button ID="Button1" runat="server" Text="Print" OnClick="Button1_Click" />

</form>

===========================

 protected void Button1_Click(object sender, EventArgs e)

    {

        Response.ContentType = "application/pdf";

        Response.AddHeader("content-disposition", "attachment;filename=Panel.pdf");

        Response.Cache.SetCacheability(HttpCacheability.NoCache);

        StringWriter stringWriter = new StringWriter();

        HtmlTextWriter htmlTextWriter = new HtmlTextWriter(stringWriter);

        

        mainDiv.RenderControl(htmlTextWriter);

        StringReader stringReader = new StringReader(stringWriter.ToString());

        Document Doc = new Document(PageSize.A4, 10f, 10f, 100f, 0f);

        HTMLWorker htmlparser = new HTMLWorker(Doc);

        PdfWriter.GetInstance(Doc, Response.OutputStream);

        Doc.Open();

        htmlparser.Parse(stringReader);

        Doc.Close();

        Response.Write(Doc);

        Response.End();

    }

Nupkg extension file from nuget package

 Convert nupkg file to zip file and you will get dll files in it. 

On the right hand side of nuget website you will get "download package" option.

How to print a print statement of sql in asp.net c# - how to call a another event in asp.net event

 using System;

using System.Data.SqlClient;

public class SqlPrintExample

{

    public static void Main(string[] args)

    {

        string connectionString = "Data Source=YourServer;Initial Catalog=YourDatabase;Integrated Security=True";

        string sqlQuery = "PRINT 'This message comes from SQL.'; SELECT GETDATE() AS CurrentDateTime;";

        using (SqlConnection connection = new SqlConnection(connectionString))

        {

            // Attach an event handler to capture InfoMessage events (including PRINT statements)

            connection.InfoMessage += Connection_InfoMessage;

or// conn.InfoMessage += new SqlInfoMessageEventHandler( Connection_InfoMessage);

            try

            {

                connection.Open();

                using (SqlCommand command = new SqlCommand(sqlQuery, connection))

                {

                    using (SqlDataReader reader = command.ExecuteReader())

                    {

                        while (reader.Read())

                        {

                            Console.WriteLine($"Current Date Time from SQL: {reader["CurrentDateTime"]}");

                        }

                    }

                }

            }

            catch (Exception ex)

            {

                Console.WriteLine($"Error: {ex.Message}");

            }

        }

    }

    private static void Connection_InfoMessage(object sender, SqlInfoMessageEventArgs e)

    {

        // Display the message from the SQL PRINT statement

        Console.WriteLine($"SQL InfoMessage: {e.Message}");

    }

}

How to create and download txt file programaticaly with asp.net c# and write content in it

   Response.Clear();

        Response.Write("This is an HttpHandler Test.");

        Response.Write("<p>Your Browser:</p>");

        Response.AddHeader("content-disposition", "attachment; filename=t.txt");

        Response.End(); 

How to download pdf file from server not on database only on server - Simplest way

//only two lines code is required that is uncommented

//Response.Clear(); // This is i am not using because response.clear is used for clearing http response (like text) but this is a file that is presently on server. Also when we create pdf of text file than we use clear function and we are getting pdf file from database (binary fromat) Response.buffer is default true so we don't need.

 Response.AddHeader("content-disposition", "attachment; filename=t.pdf"); 

 //Response.ContentType = System.Net.Mime.MediaTypeNames.Application.Pdf; 

        //"application/octet-stream"; 

        Response.WriteFile(Server.MapPath("~/App_Data/Annexure.pdf")); // File must be there on server otherwise it will give error

//Response.end is also we are not using because we are not creating pdf file , if we create pdf file or we are getting from database than we use Response.End and Response.Clear() functions.

Response.WriteFile or Response.TransmitFile use in asp.net c# - how to view pdf or text file in web browser

 It is used to show the content of any file in web browser.  This  is same as response.write but it will write the content of the file to web page. Mainly it is used to view the file content not to download the file.  Both Response.WriteFile or Response.TransmitFile  are same

example if text file than use code below

For PDF file

Response.ContentType = System.Net.Mime.MediaTypeNames.Application.Pdf;

Response.WriteFile(Server.MapPath("~/App_Data/Annexure.pdf"));

For txt file

Response.Clear(); 

     

        Response.ContentType = System.Net.Mime.MediaTypeNames.Text.Plain;  and use Text.html

        //"application/octet-stream"; 

        Response.WriteFile(Server.MapPath("~/App_Data/yash.txt"));

        Response.End(); 

or on page load, simply we can show the content of text file

Response.WriteFile("~/App_Data/" + fileName);

How to download the file using handler in asp.net c# of any format or extension - using anchor tag

  public void ProcessRequest(HttpContext context)

  {

    if (context.User.Identity.IsAuthenticated)

    {

      string filename = context.Request.QueryString["File"];

      //Validate the file name and make sure it is one that the user may access

      context.Response.Buffer = true;

      context.Response.Clear();

      context.Response.AddHeader("content-disposition", "attachment; filename=" + filename);

      context.Response.ContentType = "application/octet-stream";

//File(HelloWorld.txt) should be present on server in App_Data folder , otherwise it will show error

      context.Response.WriteFile("~/App_Data/" + filename);

    }

  }

aspx page

<a href="MyFileHandler.ashx?File=HelloWorld.txt">Click Here to Get File</a>

or 

 string fileName = context.Request.Params["File"];

 context.Response.ContentType = System.Net.Mime.MediaTypeNames.Application.Pdf; //"application/pdf"

//File(HelloWorld.txt) should be present on server in App_Data folder , otherwise it will show error

 context.Response.WriteFile("~/App_Data/" + fileName);

How to download the file using transmitfile function in asp.net c#

 Response.ContentType = "application/pdf";

Response.AppendHeader("Content-Disposition", "attachment; filename=MyFile.pdf");

//MyFile.pdf should be present in Files folder on server. other wise it will show error file not found.

Response.TransmitFile(Server.MapPath("~/Files/MyFile.pdf"));

Response.End();

reference:-https://www.c-sharpcorner.com/UploadFile/afenster/how-to-download-a-file-in-Asp-Net/

why Http Handler are used - Introduction to handler

 Http handlers are used for

Binary files

Dynamic image views

Performance-critical web pages

XML files

Minimal web pages

and these are fast and it only gives minimum response. example when you write  

Response.ContentType = "text/plain";

         //MediaTypeNames.Text.Plain

in aspx page it will give lot of information.

and when you write this in handler it will give only specific information that you want.

Also no return type of processrequest funtion in http handler

you can create other return type function in handler and also create model in handler.

How to convert bytes to string and string to bytes in c#

 

        string author = "Mahesh Chand";

        // Convert a C# string to a byte array

        byte[] bytes = Encoding.ASCII.GetBytes(author);

        foreach (byte b in bytes)

        {

            Response.Write(b );

            Response.Write(Environment.NewLine);                       

        }

bytes to string

string myString = Encoding.ASCII.GetString(bytes);

Response.Write(str);

How to convert bytes to base64string in c#

using fileupload control

 Convert.ToBase64String(fileUpload1.FileBytes);

using memory stream

 Stream fs = fileUpload1.PostedFile.InputStream;

        BinaryReader br = new BinaryReader(fs);

        

        Byte[] bytes = br.ReadBytes((int)fs.Length);

 Convert.ToBase64String(bytes );

base64 string meaning

the upper- and lower-case Roman alphabet characters (A–Z, a–z), the numerals (0–9), and the "+" and "/" symbols, with the "=" symbol as a special suffix code

How to save bytes data to image

using memory stream

MemoryStream m = new MemoryStream(bytes); 

System.Drawing.Image MyImage = System.Drawing.Image.FromStream(m);

MyImage.Save(filepathandname)

====================

using fileupload control

fileUpload1.FileBytes;

string filepathandname = Server.MapPath(string.Format("~/uploads/{0}-{1}.{2}", DateTime.Now.ToShortDateString(), Guid.NewGuid(), ".png"));

MyImage.Save(filepathandname)