How to learn c# and how to learn connection c# to sql database

DATEDIFF(HOUR, dateadd(day, datediff(day, 0, getdate()), 0)+ '01/01/1900 6:00:00 AM',  CAST(Estimated_LoadDate AS datetime))

public OracleConnection GetConnection_Oracle()
    {
        string connStr = "Data Source=(DESCRIPTION=(ADDRESS_LIST="
        + "(ADDRESS=(PROTOCOL=TCP)(HOST=Server IP Address)(PORT=Server Port Number)))"
        + "(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=etds)(INSTANCE_NAME=etds)));"
        + "User Id=redfd;Password=dfdf;";
        OracleConnection conn = new OracleConnection(connStr);
        return conn;
    }

    public DataTable GetDataTable_Oracle(string query, out string ERROR)
    {
        OracleConnection dbCon = GetConnection_Oracle();
        dbCon.Open();
        DataTable dt = new DataTable();

        OracleCommand command = new OracleCommand();
        command.Connection = dbCon;
        command.CommandType = CommandType.Text;
        command.CommandText = query;
        command.CommandTimeout = 300;
        try
        {
            OracleDataReader dr = command.ExecuteReader();
            ERROR = String.Empty;
            dt.Load(dr);
        }
        catch (Exception ex)
        {
            //ERROR = ex.ToString();
            ERROR = "";
        }
        finally
        {
            dbCon.Close();
        }
        return dt;
    }
 

 

In regard to software requirements, the .NET Framework applications can be developed, tested, and deployed under the following operating environments

I'll tell you, how to learn C# Step by step






using System; using System.Collections.Generic; using System.Data; using System.Data.SqlClient; using System.Linq; using System.Text; using System.Threading.Tasks; namespace DIGISHOP.App_Data { public class clsDataProcess { public SqlConnection getConnection() { //string connStr = @"data source=(local);database='Database';Connection Timeout=3000;Integrated Security=True"; string connStr = @"data source=SQL14;database=Database;uid=userid;password=password"; SqlConnection conn = new SqlConnection(connStr); return conn; } public DataTable GetDataTable(string query, out string ERROR) { SqlConnection dbCon = getConnection(); dbCon.Open(); DataTable dt = new DataTable(); SqlCommand command = new SqlCommand(); command.Connection = dbCon; command.CommandType = CommandType.Text; command.CommandText = query; try { SqlDataReader dr = command.ExecuteReader(); ERROR = String.Empty; dt.Load(dr); } catch (Exception ex) { ERROR = ex.ToString(); } finally { dbCon.Close(); } return dt; } public int ExecuteSql(string query, out string ERROR) { int result = 0; SqlConnection dbCon = null; try { dbCon = getConnection(); dbCon.Open(); SqlCommand command = new SqlCommand(query, dbCon); var ret = command.ExecuteScalar(); if (ret.GetType() != typeof(DBNull)) result = Int32.Parse(ret.ToString()); else result = 0; ERROR = String.Empty; } catch (Exception ex) { ERROR = ex.ToString(); } finally { dbCon.Close(); } return result; } public string UpdateCommand(string strSQl, out string ERROR) { string rt = ""; SqlConnection dbCon = null; try { dbCon = getConnection(); dbCon.Open(); SqlCommand sqlCmd = new SqlCommand(strSQl, dbCon); sqlCmd.ExecuteNonQuery(); ERROR = String.Empty; } catch (Exception ex) { ERROR = ex.ToString(); } finally { dbCon.Close(); } return rt; } } }



Main Page Add Panel


private void addPanel() { //UserLoginForm ObjUserLoginForm = new UserLoginForm(); StatusBar mainStatusBar = new StatusBar(); StatusBarPanel statusPanel = new StatusBarPanel(); // Set first panel properties and add to StatusBar statusPanel.BorderStyle = StatusBarPanelBorderStyle.Sunken; statusPanel.Text = "Application started."; statusPanel.ToolTipText = "Last Activity"; statusPanel.AutoSize = StatusBarPanelAutoSize.Contents; mainStatusBar.Panels.Add(statusPanel); StatusBarPanel unitName = new StatusBarPanel(); // Set first panel properties and add to StatusBar unitName.BorderStyle = StatusBarPanelBorderStyle.Sunken; unitName.Text = "Unit Name : " + UserLogin.UserName; unitName.AutoSize = StatusBarPanelAutoSize.Spring; mainStatusBar.Panels.Add(unitName); StatusBarPanel userName = new StatusBarPanel(); // Set first panel properties and add to StatusBar userName.BorderStyle = StatusBarPanelBorderStyle.Sunken; userName.Text = "User Name :" + UserLogin.UserName; userName.AutoSize = StatusBarPanelAutoSize.Spring; mainStatusBar.Panels.Add(userName); StatusBarPanel department = new StatusBarPanel(); // Set first panel properties and add to StatusBar department.BorderStyle = StatusBarPanelBorderStyle.Sunken; //department.Text = "Department :" + UserLoginForm.Department; department.AutoSize = StatusBarPanelAutoSize.Spring; mainStatusBar.Panels.Add(department); StatusBarPanel userrole = new StatusBarPanel(); // Set first panel properties and add to StatusBar userrole.BorderStyle = StatusBarPanelBorderStyle.Sunken; userrole.Text = "User Role : " + UserLogin.UserRole; userrole.AutoSize = StatusBarPanelAutoSize.Spring; mainStatusBar.Panels.Add(userrole); StatusBarPanel datetimePanel = new StatusBarPanel(); // Set second panel properties and add to StatusBar datetimePanel.BorderStyle = StatusBarPanelBorderStyle.Raised; datetimePanel.ToolTipText = "DateTime: " + System.DateTime.Today.ToString(); datetimePanel.Text = System.DateTime.Today.ToLongDateString(); datetimePanel.AutoSize = StatusBarPanelAutoSize.Contents; mainStatusBar.Panels.Add(datetimePanel); mainStatusBar.ShowPanels = true; Controls.Add(mainStatusBar); }