C# Class: Text file as DataBase

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Introduction

I made this class to use on a Mobile Project (.net compact framework). I tried to use SQL Compact but it gets a lot of resources.
This article will try to show you some great features of Classes in C# and to get them you should have some basic knowledge of Csharp.
We are going to create a class that will provide us some pre-made functions to use a simple text file as a Database.
A simple explanation of classes:

"In object-oriented programming, a class is a programming language construct used to group related instance variables and methods.
A method (called a function in some languages) is a set of instructions specific to a class.
Depending on the language, classes may support multiple inheritance or may require interfaces to extend other classes.
A class may indicate either specifically or abstractly what methods exist when the program executes. The latter is known as an 'abstract class'.
A class must be defined with a constructor if used as an object that will be instantiated.
However, some classes, especially those containing factory methods, are defined as static classes with no constructor.
Instead, they merely organize data hierarchically (e.g. the Math class may contain the static constant PI and the static method abs)." (Wikipedia)

Conclusion:
If we are objects, the world would have a class called Persons with many functions and properties that describe us and we would be an object of this class =)

Creating the DataBase

The columns will be separated by ';' and we don't need to set ID reference because we are going to use line number as it.
So, one database with the fields Name, LastName, Phone, Mail and Website would be like:

Renan;Duarte;323123131;renan@rodriguesduarte.net;software.botecodorenan.net
João;Carlos;14324;joao.carlos@test.com;www.joaocarlos.com
 ...

Functions

• Entries: Returns the number of lines.
• CreateConfigFile: Private function that verifies if the database exists or not and if is needed to create it or not.
• DeleteEntrie: Deletes an specific record.
• UpdateEntrie: Updates the details of an specific record.
• InsertEntrie: Insert a new record.
• Select: Search for something in a specified column. Returns IDs separated by ";", otherwise "ERROR".
• ReadEntrie: Reads one record.

Adapting the code to the custom columns

In my class, I prefer to set the columns through the code instead of doing this at the first line of the Database and in my opinion
this is better to avoid future errors. Then the headers of the functions would be:

 public int ReadEntrie(int id, ref string name, ref string lastname, ref string phone, ref string mail, ref string website)

 public int InsertEntrie(string name, string lastname, string phone, string mail, string website)

 public int UpdateEntrie(int id,string name, string lastname, string phone, string mail, string website)

Setting Properties

I created this field to get and set the path of the text file. If it exists, great, otherwise we will create this file and use it as we have setted.

  private string data_path = "";
  public string Path
  {
       get { return data_path; }
       set { data_path = value; }
  }

 /// <summary>
 /// Get or Set the path of the text file!
 /// </summary>

Creating the object

 private DataText conDB;
 private void Form1_Load(object sender, EventArgs e)
 {
 conDB = new DataText();
 conDB.Path = "C:\test.txt";
 fillComboList();
 }

The Engine

Additional functions

We can set functions with the same name but with different parameters. Like:

 public int ReadEntrie(int id, ref string name)

Points of Interest

Setting functions with the same name should be great to get a specific variable variable like, only the name or only the mail.
This code gives you some experience with classes and this would be a start of making dll's and other components =)
I haven't made any bench with this class until now but it should be perfect for small databases.

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)