Access rules are store in web.config for each folder
example like below:-
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<system.web>
<authorization>
<allow roles="Administrator" />
<deny users="*" />
</authorization>
</system.web>
</configuration>
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>
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/
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.
Computer is having data and english hindi lanuguage all time. and text is very small
but in television we have visual things , and text is very large if it had
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);
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
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)
Using fileupload field
byte[] bb = fileUpload1.FileBytes;
SqlConnection con = new SqlConnection(ConnectionString.ConString);
con.Open();
SqlCommand cmd = new SqlCommand("INSERT INTO UploadFiles (FileData, ContentType) VALUES (@filedata, @ContentType)", con);
cmd.CommandType = System.Data.CommandType.Text;
cmd.Parameters.AddWithValue("@FileData", fileUpload1.FileBytes);
cmd.Parameters.AddWithValue("@ContentType", fileUpload1.PostedFile.ContentType);
cmd.ExecuteNonQuery();
con.Close();
===============================
using binary reader
Stream fs = fileUpload1.PostedFile.InputStream;
BinaryReader br = new BinaryReader(fs);
Byte[] bytes = br.ReadBytes((int)fs.Length);
Stream fs = fileUpload1.PostedFile.InputStream;
Byte[] bytes = br.ReadBytes((int)fs.Length);
Byte[] bytes = fileUpload1.FileBytes;
MemoryStream m = new MemoryStream(bytes);
System.Drawing.Image MyImage = System.Drawing.Image.FromStream(m);
string filepathandname = Server.MapPath(string.Format("~/uploads/{0}-{1}-{2}", DateTime.Now.ToShortDateString(), Guid.NewGuid(), ".png"));
MyImage.Save(filepathandname);
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAABkAAAAOECAYAAAD5Tf2iAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAP+lSURBVHhe7N0LYFTVuTb+B1AkeIGEm0CABBAiglyD3CINoqJoKRSRNqWtSEUK51NrgVKPHD48LYLHqt8fSvEgtlJaRAqlFouKIAUBCYIXREAggVwAA0lQgQgK//2uvfbMnvueaybx+dld9m1m1r5OZr17rbdOt249LoGIiIiIiIiIiIiIiKgWqav/JSIiIiIiIiIiIiIiqjUYACEiIiIiIiIiIiIiolqHARAiIiIiIiIiIiIiIqp1GAAhIiIiIiIiIiIiIqJahwEQIiIiIiIiIiIiIiKqdep069bjkh4nIiIiIiIiIiKq1erXv0KPEVFtdf78V3qMvu3YAoSIiIiIiIiIiIiIiGodBkCIiIiIiIiIiIiIiKjWqdeixbWz9Hi1qFevHn7zmydwyy1DUFVVhaKiIr2EiIiIiIiIiIgoturVu0yP
public class ValuesController : ApiController
{
//For get all data
public IEnumerable<BookMaster> Get()
{
}
//For get by ID
public void Get(int id)
{
}
[HttpPost] // insert or add or create new
public string Post([FromBody]string value)
{
return value;
}
// PUT api/<controller>/5 update
public void Put(BookMaster bookMaster)
{
}
// DELETE api/<controller>/5
[HttpDelete]
public void Delete(int id)
{
}
>Add object datasource from controls in visual studio
> Add TypeName Property(class name .cs file) where you have get, update and delete methods.
>Click on configure data source and select dataset or typename file and you will get select insert update delete methods and click on finish and use this object datasource id in grid view or other controls.
INSERT INTO tbl_name (a,b,c) VALUES(1,2,3),(4,5,6),(7,8,9);
