.Net Skills: C#

Showing posts with label C#. Show all posts

10/08/2021

Conditional Formatting in Asp .Net Web Form Gridview

<asp:TemplateField HeaderText="Status" SortExpression="Status">
     <EditItemTemplate>
        <asp:Label ID="lblStatus" runat="server" Text='<%# Eval("Status") %>'></asp:Label>
     </EditItemTemplate>
     <ItemTemplate>
        <asp:Label ID="lblStatus" runat="server" Text='<%# Bind("Status") %>' ForeColor='<%# ((string)Eval("Status")).ToLower().Equals("open") ? System.Drawing.Color.Green : System.Drawing.Color.Red %>'></asp:Label>
     </ItemTemplate>
 </asp:TemplateField>

7/20/2021

C# Regular Expression - Windows Form Application (Username Validation)

   private void txtUsername_TextChanged(object sender, EventArgs e)
        {
            if (IsValidUsername(txtUsername.Text))
            {
                lblMsg.ForeColor = System.Drawing.Color.Green;
                lblMsg.Text = "Valid Username";
            }
            else
            {
                lblMsg.ForeColor = System.Drawing.Color.Red;
                lblMsg.Text = "Invalid Username!";
            }
        }
        public static bool IsValidUsername(string username)
        {
            //Username starts with a letter, allow letter or number, length between 7 to 12.
            string pattern;
            pattern = @"^[a-zA-Z][a-zA-Z0-9]{6,11}$";
            Regex regex = new Regex(pattern);
            return regex.IsMatch(username);
        }

12/14/2019

How To Display Selected CheckedListBox Items In TextBox Separated By Comma In C#

how to display selected checkedlistbox items in textbox separated by comma in c#

private void checkedListBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            string values = "";
            foreach (object item in checkedListBox1.CheckedItems)
            {
                if (values == "")
                    values = item.ToString();
                else values += "," + item.ToString();

            }
            textBox1.Text = values;
        }

6/30/2019

Stopwatch C# windows form

Stopwatch

Stopwatch Design Foorm

using System;
using System.Diagnostics;
using System.Windows.Forms;

namespace StopwatchProject
{
    public partial class frmStopwatch : Form
    {
        private Stopwatch mainStopwatch;
        private Stopwatch smallStopwatch; // New stopwatch for small timer  
        private Timer mainTimer;
        private Timer smallTimer; // New timer for small stopwatch  
        private int lapCount;
        private TimeSpan lastLapTime;
        public frmStopwatch()
        {
            InitializeComponent();
            mainStopwatch = new Stopwatch();
            smallStopwatch = new Stopwatch(); // Initialize small stopwatch  
            mainTimer = new Timer();
            smallTimer = new Timer(); // Initialize small timer  
            mainTimer.Interval = 100; // Update every 100ms  
            smallTimer.Interval = 100; // Update every 100ms for small timer  
            mainTimer.Tick += MainTimer_Tick;
            smallTimer.Tick += SmallTimer_Tick; // Event for small timer  
            lblTime.Text = "00:00:00.00"; // Initial time for main stopwatch  
            lblSmallTime.Text = "00:00:00.00"; // Initial time for small stopwatch  
            lapCount = 0; // Initialize lap count  
            lblLapCount.Text = "Lap Count: 0"; // Initialize lap count display  
            lastLapTime = TimeSpan.Zero; // Initialize last lap time 

            // Set up DataGridView columns  
            dataGridViewLaps.Columns.Add("LapNumber", "Lap");
            dataGridViewLaps.Columns.Add("LapTime", "Lap Times");
            dataGridViewLaps.Columns.Add("OverallTime", "Overall Time");
            dataGridViewLaps.Columns[0].AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells;
            dataGridViewLaps.Columns[1].AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells;
            dataGridViewLaps.Columns[2].AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill;

            dataGridViewLaps.MultiSelect = false;
            dataGridViewLaps.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.None;
            dataGridViewLaps.AllowUserToResizeRows = false;
            
        }
        private void MainTimer_Tick(object sender, EventArgs e)
        {
            lblTime.Text = FormatTime(mainStopwatch.Elapsed);
        }

        private void SmallTimer_Tick(object sender, EventArgs e)
        {
            lblSmallTime.Text = FormatTime(smallStopwatch.Elapsed); // Update small stopwatch display  
        }
        private string FormatTime(TimeSpan timeSpan)
        {
            return string.Format("{0:00}:{1:00}:{2:00}.{3:00}",
                timeSpan.Hours,
                timeSpan.Minutes,
                timeSpan.Seconds,
                timeSpan.Milliseconds / 10);
        }

        private void btnStartStop_Click(object sender, EventArgs e)
        {
            if (mainStopwatch.IsRunning)
            {
                mainStopwatch.Stop();
                mainTimer.Stop();
                smallStopwatch.Stop();
                smallTimer.Stop();
                btnStartStop.Text = "Start";
            }
            else
            {
                mainStopwatch.Start();
                mainTimer.Start();
                smallStopwatch.Start();
                smallTimer.Start();
                btnStartStop.Text = "Stop";
            }
        }

        private void btnReset_Click(object sender, EventArgs e)
        {
            mainStopwatch.Reset();
            lblTime.Text = "00:00:00.00";
            dataGridViewLaps.Rows.Clear(); // Clear the DataGridView
            lapCount = 0; // Reset lap count  
            lblLapCount.Text = "Lap Count: 0"; // Update lap count display  
            btnStartStop.Text = "Start";
            mainTimer.Stop();
            lastLapTime = TimeSpan.Zero; // Reset last lap time  

            // Reset small stopwatch  
            smallStopwatch.Reset();
            lblSmallTime.Text = "00:00:00.00"; // Reset small stopwatch display  
            smallTimer.Stop(); // Stop small timer   
            lblSmallTime.Visible = false;
        }

        private void btnLap_Click(object sender, EventArgs e)
        {
            if (mainStopwatch.IsRunning)
            {
                lapCount++; // Increment lap count  
                TimeSpan currentLapTime = mainStopwatch.Elapsed - lastLapTime; // Calculate lap time  
                lastLapTime = mainStopwatch.Elapsed; // Update last lap time  
                string lapTime = FormatTime(currentLapTime); // Get the formatted lap time  
                string overallTime = FormatTime(mainStopwatch.Elapsed); // Get the overall time  

                // Add a new row to the DataGridView  
                dataGridViewLaps.Rows.Insert(0, lapCount, lapTime, overallTime);

                dataGridViewLaps.ClearSelection();

                lblLapCount.Text = $"Lap Count: {lapCount}"; // Update lap count display  

                // Reset and start the small stopwatch  
                smallStopwatch.Reset();
                smallStopwatch.Start();
                smallTimer.Start(); // Start small timer  
                lblSmallTime.Visible=true;
            }
        }
    }
}

5/15/2017

Prevent Form From Closing By Displaying A Message Box In Windows Form C#

Prevent Duplicate MDI Children Forms In Windows Form c#

Prevent duplicate MDI children forms in Windows form c#

2/01/2016

C# User Defined RandomStringGenerator()

public partial class Signup : System.Web.UI.Page
{
   private string GenAuthCode(string username)
    {
        RandomStringGenerator myrsg = new RandomStringGenerator();
        return myrsg.NextString(20);
    }
}
public class RandomStringGenerator
{
    private Random r;
    const string Uppercase = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    const string Lowercase = "abcdefghijklmnopqrstuvwxyz";
    const string Numbers = "0123456789";
    const string Symbols = @"~`!@#$%^&()-_=+<>?:,./\[]{}'";
    public RandomStringGenerator()
    {
        r = new Random();
    }
    public RandomStringGenerator(int seed)
    {
        r = new Random(seed);
    }
    public virtual string NextString(int Length)
    {
        return NextString(Length, true, true, true, true);
    }
    public virtual string NextString(int Length, bool lowerCase, bool upperCase, bool numbers, bool symbols)
    {
        char[] charArray = new char[Length];
        string charpool = string.Empty;

        //Build character pool
        if (lowerCase)
            charpool += lowerCase;
        if (upperCase)
            charpool += upperCase;
        if (numbers)
            charpool += numbers;
        if (symbols)
            charpool += symbols;

        //Build the output character array
        for (int i = 0; i < charArray.Length; i++)
        {
            //Pick the randim integer in the character pool
            int index = r.Next(0, charpool.Length);

            //Set it to the output character array
            charArray[i] = charpool[index];
        }
        return new string(charArray);

    }
}

9/10/2015

C# Console Application (Bank)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Bank
{
    class Errors:Exception
    {
        public Errors(string ErrorMsg)
            : base(ErrorMsg)
        {

        }

    }
    class Accounts
    {
        public int[] index;
        public string Acc_no = "", C_name = "", C_add = "";
        public double Balance = 0;
        int Age;
        public Accounts() { }
        public Accounts(String Acc_no, string C_name,int Age, String C_add, double Balance)
        {
            //int[] index,
            //this.index = index;
            this.Acc_no = Acc_no;
            this.C_name = C_name;
            this.C_add = C_add;
            this.Balance=Balance;
        }

        public int Create_Acc()
        {
            //for (int i = 0; i < index.Length;i++ )
            //{

            //}
            try
            {
                Console.Write("Enter The Account Number:\t");
                Acc_no = Console.ReadLine();
                if (Acc_no == null)
                    throw new Errors("You must enter the Account number!");
                
                Console.Write("Enter The Customer Name:\t");
                C_name = Console.ReadLine();
                if (C_name == null)
                    throw new Errors("You must enter the Account number!");
                
                Console.Write("Age:\t\t\t\t");
                Age = int.Parse(Console.ReadLine());
                if (Age <=0)
                    throw new Errors("You must enter the Account number!");
                
                Console.Write("Enter The Address:\t\t");
                C_add = Console.ReadLine();
                if (C_add == null)
                    throw new Errors("You must enter the Account number!");
                
                Console.Write("Deposite amount:\t\t");
                Balance = double.Parse(Console.ReadLine());
                if (Balance <= 0)
                    throw new Errors("You must enter the Account number!");
            }
            catch(Errors e)
            {
                Console.Write(e.Message);
            }
            
            return 1;

        }

        public void Acc_Availability(string Acc_num)
        {
            if (Acc_no.Equals(Acc_num))
            {
                Console.WriteLine("-----------------------------****************-----------------------------");
                Console.WriteLine("Account Number:\t"+Acc_no);
                Console.WriteLine("Name:\t\t"+C_name);
                Console.WriteLine("Age:\t\t" + Age);
                Console.WriteLine("Address:\t" + C_add);
                Console.WriteLine("Balance: \t$" + Balance);
                Console.WriteLine("-----------------------------****************-----------------------------");
            }
            else
            {
                Console.WriteLine("Account does not exist!");
            }
        }
        public void Deposite(string Acc_num)
        {
            try
            {


                if (Acc_no.Equals(Acc_num))
                {
                    Console.Write("Enter the amount:\t\t");
                    int Amount = int.Parse(Console.ReadLine());
                    if (Amount <= 0)
                        throw new Errors("Amount must be larger than $0");
                    else
                        this.Balance = Balance + Amount;

                    Console.WriteLine("-----------------------------****************-----------------------------");
                    Console.WriteLine("Balance is:  $" + Balance);
                    Console.WriteLine("-----------------------------****************-----------------------------");
                }
                else
                {
                    Console.WriteLine("Account does not exist!");
                }
            }
            catch(Errors e)
            {
                Console.BackgroundColor = ConsoleColor.White;
                Console.ForegroundColor = ConsoleColor.Red;
                Console.WriteLine(e.Message);
                Console.BackgroundColor = ConsoleColor.Black;
                Console.ForegroundColor = ConsoleColor.White;
            }
        }
        public void Withdraw(string Acc_num)
        {
            if (Acc_no.Equals(Acc_num))
            {
                Console.Write("Enter the amount:\t\t");
                int Amount = int.Parse(Console.ReadLine());
                if (Balance == 0)
                {
                    Console.WriteLine("Insufficient balance");

                }
                else if (Amount > Balance)
                {
                    Console.WriteLine("Insufficient balance");
                }
                else
                {
                    Balance = Balance - Amount;
                    Console.WriteLine("Balance: $"+Balance);
                }
            }
            else
            {
                Console.WriteLine("Account does not exist!");
            }
        }
        public void Balenquiry()
        {
            Console.WriteLine("Your baance is: " + Balance);
        }

    }
    class Program
    {
        static void Main(string[] args)
        {
            //char ch;
            int result;
            String Acc_num,ch;
            //double depositeamount;
            //double withdrawamount;

            Accounts Acc = new Accounts();
            //try
            //{

           
                for (; ; )
                {
                    Console.WriteLine("----------------------------------------------------------------------");
                    Console.WriteLine("1.New Acoount\t2.Enquiry\t3.Deposit\t4.Withdraw\t5.Exit");
                    Console.WriteLine("----------------------------------------------------------------------");
                    ch = Console.ReadLine();
                    
                    switch (ch)
                    {
                        case "1": 
                            
                            result=Acc.Create_Acc();
                            if(result==1)
                            {
                                Console.WriteLine("Account number \"{0}\" Created Successfuly", Acc.Acc_no);
                            }
                            else
                            {
                                Console.WriteLine("Account could not be created! Try again.");
                            }
                            
                            break;

                        case "2":
                            
                            Console.Write("Enter the Account Number:\t");
                            Acc_num=Console.ReadLine();
                            Acc.Acc_Availability(Acc_num);
                            break;

                        case "3":
                            
                            Console.Write("Enter the Account Number:\t");
                            Acc_num=Console.ReadLine();
                            Acc.Deposite(Acc_num);
                            break;

                        case "4":
                            
                            Console.Write("Enter The Customer Account Number:  ");
                            Acc_num = Console.ReadLine();
                            Acc.Withdraw(Acc_num);
                            break;
                        
                        case "5": 
                            
                            System.Environment.Exit(0);
                            break;

                        default:
                            
                            Console.WriteLine("invalid choice!");
                            break;
                    }
                }
             }
            //catch(Errors e)
            //{
            //    Console.WriteLine(e.Message);
            //}
            //}
             
        
    }
}

6/01/2015

Asp .Net C# (ADO .NET)

SqlDataReader

ExceuteNonQuery(Insert,Update,Delete)

ExceuteNonQuery (Insert)

ExceuteReader (1)

ExceuteReader (2)

ExecuteScalar

1/04/2015

C# Dictionary

using System.Collections.Generic;  
using System.ComponentModel;  
using System.Data;  
using System.Drawing;  
using System.Linq;  
using System.Text;
using System.Windows.Forms;  
using System.Data.OleDb;
namespace KDictionary  
{
  public partial class Dic : Form
{
  private OleDbConnection cn;
  private OleDbDataReader reader;
  private OleDbCommand com;
  private DataSet rs;
  private OleDbDataAdapter ad;
      public Dic()
  {
  InitializeComponent();
  }
    private void Dic_Resize(object sender, EventArgs e)
  {
  //Adjust listbox and textbox heights when the form resizes
  //Dic dictionary = new Dic();
  if (this.WindowState == FormWindowState.Maximized)
  {
  Lstterms.Height = this.Height;  
        Txtresult.Height = this.Height;
  Txtresult.Width = this.Width ;
  }
}   
 private void Dic_Load(object sender, EventArgs e)
  {
  myconnect();
  this.Resize+= new EventHandler(Dic_Resize);
  this.FormClosed += new FormClosedEventHandler(Dic_FormClosed);
   }
 
       private void myconnect()
        {
  try
  {
   //connect to database
  rs = new DataSet();
  cn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" +   Application.StartupPath + "\\data.mdb;");
  cn.Open();
  ad = new OleDbDataAdapter("SELECT * FROM Tblterms ORDER BY Enterms", cn);
  ad.Fill(rs, "Tblterms");
  com = new OleDbCommand("SELECT Enterms FROM Tblterms ORDER BY Enterms", cn);
  reader = com.ExecuteReader();
  //clear list  
        Lstterms.Items.Clear();
  //clear txtresult
  Txtresult.Text = "";
  while (reader.Read())  {
  Lstterms.Items.Add(reader[0].ToString());
  } 
        } 
 catch (Exception ex)
        {
        }
  Txtbox.Focus();
       }
  private void Txtbox_TextChanged(object sender, EventArgs e)  
        {
  int i;
  DataRow dr;
  try  { 
 for (i = 0; i <= Lstterms.Items.Count - 1; i++)
  { 
  if (Txtbox.Text.Trim().ToUpper() == Lstterms.Items[i].ToString().ToUpper().Substring(0,   Txtbox.TextLength))
  { 
 //Select matched term  
        Lstterms.SelectedIndex = i;
  //Display translation  
        dr = rs.Tables[0].Rows[i];
  Txtresult.Clear();
  Txtresult.Text = dr[1].ToString().Trim();
  highlight(); 
 break;
  } 
 } 
 }  
       catch (Exception ex)
       {
       } 
      }    
       private void Lstterms_SelectedIndexChanged(object sender, EventArgs e)
  {
  DataRow dr;
  dr = rs.Tables[0].Rows[Lstterms.SelectedIndex];
  Txtresult.Clear(); //clear result
  Txtresult.Text =dr[1].ToString().Trim ();
  highlight(); 
 }  
       private void highlight()  
       {    
         try  {
   char[] c = Txtresult.Text.ToString().ToCharArray();  //coloring v.,a., and n.
  int i; 
 for (i = 1; i <= Txtresult.Text.ToString().Length - 2; i++)
  { 
 if ((c[i] == '.' && c[i - 1] == 'v') || (c[i] == '.' && c[1 - 1] == 'a') ||   (c[i] == '.' && c[i - 1] == 'n'))  
//If (((c[i] == ".") && (c[i - 1] == "v")) || ((c[i] == ".") && (c[i - 1] ==   "a")) || ((c[i] == ".") && (c[i - 1] =="n"))) 
 {
  Txtresult.SelectionStart = i - 1;
  Txtresult.SelectionLength = 2;
  Txtresult.SelectionColor = Color.Red; 
   } 
   } 
 //coloring adj., adv. 
 for (i = 3; i <= Txtresult.Text.ToString().Length - 1; i++)
  { 
if ((c[i] == '.' && c[i - 1] == 'j' && c[i - 2] == 'd') || (c[i] == '.' &&   c[i - 1] == 'g' && c[i - 2] == 'i') || (c[i] == '.' && c[i - 1] == 'v' && c[i   - 2] == 'd'))
  {  
Txtresult.SelectionStart = i - 3;
  Txtresult.SelectionLength = 4;
  Txtresult.SelectionColor = Color.Red;
  }
    }
  //coloring Khmer character
    for (i = 0; i <= Txtresult.Text.ToString().Length - 1; i++) 
 { 
   if ((int)c[i] > 127)
  {  
       //int ix = (int)c[i];  
       //MessageBox.Show("Hello"+ix);
  Txtresult.SelectionStart = i;
  Txtresult.SelectionLength = 1;
  Txtresult.SelectionColor = Color.Black; 
 } 
 } 
     } 
 catch (Exception ex) { } 
 } 
 private void closeToolStripMenuItem_Click(object sender, EventArgs e)
  { 
  Close();
   }  
  private void menuStrip1_ItemClicked(object sender,ToolStripItemClickedEventArgs e) 
 {
 
 } 
 private void Dic_FormClosed(object sender,EventArgs e) 
 {  
         cn.Close();  
         cn = null;  
         com = null;  
         reader = null;  
         ad = null;  
         rs = null; 
 } 
  }
  }

9/18/2014

Date and Time Format Strings in C#

private void dateTimePicker1_ValueChanged(object sender, EventArgs e)  
     {  
       label15.Text = dateTimePicker1.Value.ToString("d");  
       label16.Text = dateTimePicker1.Value.ToString("D");  
       label17.Text = dateTimePicker1.Value.ToString("f");  
       label18.Text = dateTimePicker1.Value.ToString("F");  
       label19.Text = dateTimePicker1.Value.ToString("g");  
       label20.Text = dateTimePicker1.Value.ToString("G");  
       label21.Text = dateTimePicker1.Value.ToString("m");  
       label22.Text = dateTimePicker1.Value.ToString("r");  
       label23.Text = dateTimePicker1.Value.ToString("s");  
       label24.Text = dateTimePicker1.Value.ToString("t");  
       label25.Text = dateTimePicker1.Value.ToString("T");  
       label26.Text = dateTimePicker1.Value.ToString("u");  
       label27.Text = dateTimePicker1.Value.ToString("U");  
       label28.Text = dateTimePicker1.Value.ToString("y");  
     }

7/10/2014

Increment the value of Qty if row with the same data already exists in DataGridView

private void btn_Add_Click(object sender, EventArgs e)  
     {  
       //Boolean value to check if the DataGridView has the same value.  
       bool Found = false;  
       double total = Convert.ToDouble(txt_Price.Text) * 1;  
       if (dataGridView1.Rows.Count > 0)  
       {  
         //Check if the product Name exists with the same Price  
         foreach (DataGridViewRow row in dataGridView1.Rows)  
         {  
           if (Convert.ToString(row.Cells[0].Value) == txt_Name.Text && Convert.ToString(row.Cells[2].Value) == txt_Price.Text)  
           {  
             //Update the Quantity of the found row  
             row.Cells[1].Value = Convert.ToString(1 + Convert.ToInt16(row.Cells[1].Value));  
             row.Cells[3].Value = Convert.ToDouble(row.Cells[1].Value) * Convert.ToDouble(row.Cells[2].Value);  
             Found = true;  
           }  
         }  
         if (!Found)  
         {  
           //Add the row to DataGridView if data not present  
           dataGridView1.Rows.Add( txt_Name.Text,1, txt_Price.Text,total);  
         }  
       }  
       else  
       {  
         //Add the first row to DataGridView if there is no row  
         dataGridView1.Rows.Add( txt_Name.Text, 1, txt_Price.Text,total);  
       }  
     }