Tuesday, May 25, 2021

Base64 - Encoding and Decoding s String

The following class can be used to encode a string or decode an encoded string. 


   public static class Base64  
   {  
     public static string Encode(this System.Text.Encoding encoding, string textValue)  
     {  
       if (textValue == null)  
       {  
         return null;  
       }  
       try  
       {  
         byte[] textAsBytes = encoding.GetBytes(textValue);  
         return System.Convert.ToBase64String(textAsBytes);  
       }  
       catch (Exception)  
       {  
         return textValue;  
       }        
     }  
     public static string Decode(this System.Text.Encoding encoding, string encodedTextValue)  
     {  
       if (encodedTextValue == null)  
       {  
         return null;  
       }  
       try  
       {  
         byte[] textAsBytes = System.Convert.FromBase64String(encodedTextValue);  
         return encoding.GetString(textAsBytes);  
       }  
       catch (Exception)  
       {  
         return encodedTextValue;  
       }        
     }  
   }  

So, you can refer this as below;



 EncodingForBase64.DecodeBase64(Encoding.UTF8, yourtextvalue);  

Happy coding...

Convert an Image to Base64

Base64 encoded files are larger than the original. The advantage lies in not having to open another connection and make a HTTP request to the server for the image. This benefit is lost very quickly so there's only an advantage for large numbers of very tiny individual images.

Link to the Question

However we may still need to convert an image to base64 on the way to display our data on HTML page. Assuming you have a class that represent all the necessary details, here is how you can have an additional property to the class that converts images to base64.




     public string imageBase64  
     {  
       get  
       {  
         using (var client = new WebClient())  
         {  
           byte[] dataBytes = client.DownloadData(new Uri(image));  
           string encodedFileAsBase64 = Convert.ToBase64String(dataBytes);  
           return "data:image/jpeg;base64," + encodedFileAsBase64;  
         }  
       }  
     }  

Copy this and try it in your code. it will generate your html image tag as below.


Happy Coding...


Sunday, February 14, 2021

Writing a class to access mongo db end points in C#

Not knowing MongoDB? Read it here: 

https://en.wikipedia.org/wiki/MongoDB

"MongoDB is a source-available cross-platform document-oriented database program. Classified as a NoSQL database program, MongoDB uses JSON-like documents with optional schemas. "

Today we talk about how to write a common class to access end points ( Hosted seperately) that allow us to access MongoDB collection. You can read / write collections through this.

Lets go straight to the code:


   public class MongoService  
   {  
     public XmlDocument Select(Method method, string ServiceAddress, Dictionary<string, string> Header, Dictionary<string, object> Parameter)  
     {  
       var client = new RestClient(ServiceAddress);  
       client.Timeout = -1;  
       var request = new RestRequest(method);  
       foreach (var h in Header)  
         request.AddHeader(h.Key, h.Value);  
       foreach (var p in Parameter)  
         request.AddParameter(p.Key, p.Value);  
       IRestResponse response = client.Execute(request);  
       if (string.IsNullOrEmpty(response.Content))  
         return null;  
       var node = JsonConvert.DeserializeXNode(response.Content, "Root");  
       string xml = node.ToString();  
       XmlDocument doc = new XmlDocument();  
       doc.LoadXml(xml);  
       return doc;  
     }  
     public string Select<T>(Method method, string ServiceAddress, Dictionary<string, string> Header, Dictionary<string, object> Parameter)  
     {  
       var client = new RestClient(ServiceAddress);  
       client.Timeout = -1;  
       var request = new RestRequest(method);  
       foreach (var h in Header)  
         request.AddHeader(h.Key, h.Value);  
       foreach (var p in Parameter)  
         request.AddParameter(p.Key, p.Value);  
       IRestResponse response = client.Execute(request);  
       return response.Content;  
     }  
     public string Select<T>(Method method, string ServiceAddress, Dictionary<string, string> Header)  
     {  
       var client = new RestClient(ServiceAddress);  
       client.Timeout = -1;  
       var request = new RestRequest(method);  
       foreach (var h in Header)  
         request.AddHeader(h.Key, h.Value);  
       IRestResponse response = client.Execute(request);  
       return response.Content;  
     }  
     public string Save<T>(Method method, string ServiceAddress, Dictionary<string, string> Header, Dictionary<string, object> Parameter)  
     {  
       var client = new RestClient(ServiceAddress);  
       client.Timeout = -1;  
       var request = new RestRequest(method);  
       foreach (var h in Header)  
         request.AddHeader(h.Key, h.Value);  
       foreach (var p in Parameter)  
         request.AddParameter(p.Key, p.Value);  
       IRestResponse response = client.Execute(request);  
       return response.Content;  
     }  
     public string Update<T>(Method method, string ServiceAddress, Dictionary<string, string> Header, Dictionary<string, object> Parameter)  
     {  
       var client = new RestClient(ServiceAddress);  
       client.Timeout = -1;  
       var request = new RestRequest(method);  
       foreach (var h in Header)  
         request.AddHeader(h.Key, h.Value);  
       foreach (var p in Parameter)  
         request.AddParameter(p.Key, p.Value);  
       IRestResponse response = client.Execute(request);  
       return response.Content;  
     }  
     public string Delete<T>(Method method, string ServiceAddress, Dictionary<string, string> Header, Dictionary<string, object> Parameter)  
     {  
       var client = new RestClient(ServiceAddress);  
       client.Timeout = -1;  
       var request = new RestRequest(method);  
       foreach (var h in Header)  
         request.AddHeader(h.Key, h.Value);  
       foreach (var p in Parameter)  
         request.AddParameter(p.Key, p.Value);  
       IRestResponse response = client.Execute(request);  
       return response.Content;  
     }  
   }  


The MongoService class has the following methods.

public XmlDocument Select(Method method, string ServiceAddress, Dictionary<string, string> Header, Dictionary<string, object> Parameter)  

This return the result as an xml document.

The parameters contain;

  • Method
  • ServiceAddress
  • Header
  • Parameter

The method is the restsharp method as it is GET or POST or any other.

Service address is the service address.

Header is the Dictionary of strings for headers.

Parameter is the Dictionary of string and object values for the parameters.

Using this class will help to ease with dealing the end points.

Happy coding.





Tuesday, February 9, 2021

Creating country flag emoji from country code - c#

Sometimes you might need to show the country flag as an icon or imoji in your webpage. But we don't need to host images of country flags anywhere which we can create images from the code itself. look at the below code.

 public static string CountryCodeToFlag(this string country)  
     {  
       return string.Concat(country.ToUpper().Select(x => char.ConvertFromUtf32(x + 0x1F1A5)));  
     }  

This is an extension method. so we can use it as below.

 "us".CountryCodeToFlag()  

The result will look like below,

Happy coding...


Saturday, July 4, 2020

c# - App.config - read and write - easy way

Let's discuss about how we can read and write App.Config file in a easy way. Before that if you need to know more about what is this file, read this post https://blog.submain.com/app-config-basics-best-practices/

Lets get back to code.

     public static bool UpdateAppSettings(string key, string value)  
     {  
       try  
       {  
         var configFile = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);  
         var settings = configFile.AppSettings.Settings;  
         if (settings[key] == null)  
         {  
           settings.Add(key, value);  
         }  
         else  
         {  
           settings[key].Value = value;  
         }  
         configFile.Save(ConfigurationSaveMode.Modified);  
         ConfigurationManager.RefreshSection(configFile.AppSettings.SectionInformation.Name);  
         return true;  
       }  
       catch (Exception)  
       {  
         throw;  
       }  
     }  

     public static string ReadAppSetting(string key)  
     {  
       try  
       {  
         return ConfigurationManager.AppSettings[key];  
       }  
       catch (Exception)  
       {  
         throw;  
       }  
     }  


UpdateAppSettings and ReadAppSetting are two methods we use. lets say we have a config value like below.



We can read and update this values as this.


 public static string ConString { get { return ReadAppSetting("ConString"); } set { UpdateAppSettings("ConString", value); } }  


Hope you can get this applied to your need too.
Happy coding.

Thursday, June 25, 2020

Creating Images from Text in C#

Sometimes you might need to create images from text. Following method can be used to do that.

 public static Image DrawText(String text, Font font, Color textColor, Color backColor)  
     {        
       Image img = new Bitmap(1, 1);  
       Graphics drawing = Graphics.FromImage(img);  
       SizeF textSize = drawing.MeasureString(text, font);  
       img.Dispose();  
       drawing.Dispose();  
       img = new Bitmap((int)textSize.Width, (int)textSize.Height);  
       drawing = Graphics.FromImage(img);  
       drawing.Clear(backColor);  
       drawing.SmoothingMode = SmoothingMode.AntiAlias;  
       drawing.InterpolationMode = InterpolationMode.HighQualityBicubic;  
       drawing.PixelOffsetMode = PixelOffsetMode.HighQuality;  
       drawing.TextRenderingHint = TextRenderingHint.SingleBitPerPixelGridFit;  
       Brush textBrush = new SolidBrush(textColor);  
       drawing.DrawString(text, font, textBrush, 0, 0);  
       drawing.Save();  
       textBrush.Dispose();  
       drawing.Dispose();  
       return img;  
     }  

Such scenario can be applied to a website like below, The logo is created from a text there.




Happy coding.
Copy this code...and try

MS Excel Reader with No dependancy in C# - Reading file horizontally

This is a cool nuget package that you can use to read excel files into dataset just like how you query the database. Very simple and no dependancy. What you need is to install the add the following 2 nuget packages into your solution.



These are the URLs,
https://www.nuget.org/packages/ExcelDataReader/

https://www.nuget.org/packages/ExcelDataReader.DataSet/

Then you can read the file as below. Note that this code will read your file horizontally. Meaning column by column.

 try {  
  OpenFileDialog of = new OpenFileDialog(); of .Filter = "Excel Files|*.xls;*.xlsx;*.xlsm"; of .ShowDialog();  
  var FilePath = of .FileName;  
  if (File.Exists(FilePath)) {  
  try {  
   using(var stream = File.Open(FilePath, FileMode.Open, FileAccess.Read)) {  
   using(var reader = ExcelReaderFactory.CreateReader(stream)) {  
    var result = reader.AsDataSet();  
    if (result != null && result.Tables != null && result.Tables.Count > 0) {  
    rowCountMultiple = result.Tables[0].Rows.Count;  
    colCountMultiple = result.Tables[0].Columns.Count;  
    List < string > valueList;  
    string token, value;  
    listTokensForPageMultiple = new Dictionary < int, List < string >> ();  
    for (int c = 0; c < colCountMultiple; c++) {  
     valueList = new List < string > ();  
     token = result.Tables[0].Rows[0][c].ToString();  
     for (int r = 0; r < rowCountMultiple; r++) {  
     value = result.Tables[0].Rows[r][c].ToString();  
     valueList.Add(value);  
     }  
     listTokensForPageMultiple.Add(c, valueList);  
    }  
    }  
   }  
   }  
  } catch (Exception ex) {  
   Common.Error(ex.Message, ex);  
  } finally {  
   GC.Collect();  
  }  

Copy and paste this code and try.
Happy coding...