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...

Wednesday, May 13, 2020

Export array of data to excel in C#

Most of the time, we need to deal with data that also need to export to excel. So, the following method can export your string array to excel. lets have a look :

     public static bool ExportArrayToExcel(List<string[]> data, string filename, string[] headers=null, bool flOpenFile = false)  
     {  
       bool flExported = false;  
       try  
       {  
         SaveFileDialog sfd = new SaveFileDialog();  
         sfd.Filter = "Excel Documents (*.xls)|*.xls";  
         sfd.FileName = filename;  
         if (sfd.ShowDialog() == DialogResult.OK)  
         {  
           string stOutput = "";  
           string sHeaders = "";  
           if (headers.Count() > 0)  
           {  
             for (int j = 0; j < headers.Count(); j++)  
               sHeaders = sHeaders.ToString() + Convert.ToString(headers[j]) + "\t";  
             stOutput += sHeaders + "\r\n";  
           }  
           for (int i = 0; i < data.Count; i++)  
           {  
             string stLine = "";  
             for (int j = 0; j < data[i].Count(); j++)  
               stLine = stLine.ToString() + Convert.ToString(data[i][j]) + "\t";  
             stOutput += stLine + "\r\n";  
           }  
           Encoding utf16 = Encoding.GetEncoding(1254);  
           byte[] output = utf16.GetBytes(stOutput);  
           FileStream fs = new FileStream(sfd.FileName, FileMode.Create);  
           BinaryWriter bw = new BinaryWriter(fs);  
           bw.Write(output, 0, output.Length);   
           bw.Flush();  
           bw.Close();  
           fs.Close();  
           if (flOpenFile)  
           {  
             Process.Start(sfd.FileName);  
           }  
         }  
       }  
       catch (Exception)  
       {  
         throw;  
       }  
       return flExported;  
     }  

copy and paste and try.

happy coding..

Monday, May 4, 2020

C# MongoDB Data Access Layer Explained

In our previous post, we discussed about writing a data access layer for mongodb. So, let's discuss a bit about each method.

     public bool Insert<T>(T RecordToInsert)  
     {  
       return Insert<T>(typeof(T).Name, RecordToInsert);  
     }  
     public bool Insert<T>(string TableName, T RecordToInsert)  
     {  
       Connect();  
       var collection = mongoDatabase.GetCollection<T>(TableName);  
       collection.InsertOne(RecordToInsert);  
       return true;  
     } 

This methods are used to insert records to a specific collection. The T is a generic type which you can pass any entity. For example, lets say you have a Person class. and you are going to add a new person. So what you need is to pass the Person object  to this method. Normally collections are named as the class name so that it's not going to be clear.

 public bool Insert(Person p)  
     {  
       return dal.Insert(p);         
     }  

The sample Person class will looks like below. You must have the
[BsonId]      
     public ObjectId _id { get; set; } 

so that the MongoDB can keep the unique code generated upon saving a new person.

   public class Person  
   {  
     private int _idPerson;  
     private string _mobileNumber;  
     private string _lastName;  
     private string _firstName;  
     private string _username;  
     private string _password;  
     private DateTime _lastModified;  
     [BsonId]      
     public ObjectId _id { get; set; }  
     public int IdPerson  
     {  
       get { return _idPerson; }  
       set { _idPerson = value; }  
     }  
     public string FirstName  
     {  
       get { return _firstName; }  
       set { _firstName = value; }  
     }      
     public string LastName  
     {  
       get { return _lastName; }  
       set { _lastName = value; }  
     }  
     public string MobileNumber  
     {  
       get { return _mobileNumber; }  
       set { _mobileNumber = value; }  
     }  
     public string Username  
     {  
       get { return _username; }  
       set { _username = value; }  
     }  
     public string Password  
     {  
       get { return _password; }  
       set { _password = value; }  
     }      
     public DateTime LastModified  
     {  
       get { return _lastModified; }  
       set { _lastModified = value; }  
     }      
   }  

Lets see how we can use replace function to update/replace a specific record.

     public bool Replace<T>(T RecordToUpsert, string UpdateColumnName, BsonValue WhereValue)  
     {  
       return Replace<T>(typeof(T).Name, RecordToUpsert, UpdateColumnName, WhereValue);  
     }  
     public bool Replace<T>(string TableName, T RecordToUpsert, string UpdateColumnName, BsonValue WhereValue)  
     {  
       Connect();  
       var filter = Builders<T>.Filter.Eq(UpdateColumnName, WhereValue);        
       var collection = mongoDatabase.GetCollection<T>(TableName);        
       var result = collection.ReplaceOne(filter, RecordToUpsert);  
       return result.IsAcknowledged;  
     }  

This 2 methods will help with our update / replace of persons as below.

     public bool Replace(Person p)  
     {  
       return dal.Replace(p, "IdPerson", p.IdPerson);  
     }  

Here we have the p as Person object that has all the existing and modified data. Also we use IdPerson as the key to update the person.

So, the deletion is done as below.
     public void Delete<T>(BsonValue WhereValue)  
     {  
       Delete<T>(typeof(T).Name, "_id", WhereValue);  
     }  
     public void Delete<T>(string DeleteColumnName, BsonValue WhereValue)  
     {  
       Delete<T>(typeof(T).Name, DeleteColumnName, WhereValue);  
     }      
     public void Delete<T>(string TableName, string DeleteColumnName, BsonValue WhereValue)  
     {  
       Connect();  
       var collection = mongoDatabase.GetCollection<T>(TableName);  
       var filter = Builders<T>.Filter.Eq(DeleteColumnName, WhereValue);  
       collection.DeleteOne(filter);  
     }

So, you can either use _id which is MongoDB ID value of  the record to delete or you can pass a matching attribute with it's value to delete.

Finally, the selection can be done like this;

     public List<T> Select<T>()  
     {  
       return Select<T>(typeof(T).Name);  
     }  
     public List<T> Select<T>(string TableName)  
     {  
       Connect();  
       var collection = mongoDatabase.GetCollection<T>(TableName);  
       return collection.Find(new BsonDocument()).ToList();  
     }  
     public List<T> Select<T>(BsonValue WhereValue, string SelectColumnName = null)  
     {  
       Connect();  
       if (string.IsNullOrEmpty(SelectColumnName))  
         SelectColumnName = "_id";  
       return Select<T>(typeof(T).Name, SelectColumnName, WhereValue);  
     }  
     public List<T> Select<T>(string TableName, string SelectColumnName, BsonValue WhereValue)  
     {  
       Connect();  
       var collection = mongoDatabase.GetCollection<T>(TableName);  
       var filter = Builders<T>.Filter.Eq(SelectColumnName, WhereValue);  
       return collection.Find(filter).ToList();  
     }

Methods can  be used as ;

     public List<Person> Select()  
     {  
       return dal.Select<Person>();  
     }  

The matching type Person will return a list of persons from the collection.

So, try using these methods and if any let me know.
Happy coding...