C# İle Örnekler #56

C# Veritabanı Müşteri Bakiye ve Tahsilat İşlemleri

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.OleDb;
 
 
namespace MusteriHesap
{
    public partial class Form1 : Form
    {
        OleDbConnection con= new OleDbConnection("Provider=Microsoft.ACE.OleDb.12.0;Data Source=dbMusteri.accdb");
        OleDbCommand cmd;
        OleDbDataReader dr;
 
        public Form1()
        {
            InitializeComponent();
           
        }
 
        void Doldur()
        {
 
            listBox1.Items.Clear();
            listBox1.Items.Add("Müşteri No\tBakiye");
            listBox1.Items.Add("==========================");
            cmd = new OleDbCommand();
            con.Open();
            cmd.Connection = con;
            cmd.CommandText = "Select *From Hesap";
            dr = cmd.ExecuteReader();
            while (dr.Read())
            {
                listBox1.Items.Add(dr[0] + "\t\t" + dr[1]);
            }
            con.Close();
        }
 
        public double BakiyeGetir(int mno) 
        {
            con.Open();
            double musteribakiye = 0;
            cmd.CommandText = "Select * From Hesap where musterino=" + mno + "";
            dr = cmd.ExecuteReader();
            while (dr.Read())
            {
                musteribakiye = Convert.ToDouble(dr[1]);
 
            }
            con.Close();
            return musteribakiye;
 
        }
 
 
 
        private void Form1_Load(object sender, EventArgs e)
        {
            Doldur();
        }
 
 
 
        private void button1_Click(object sender, EventArgs e)
        {
            int mno=Convert.ToInt32(textBox1.Text);
            double cekilen=Convert.ToDouble(textBox2.Text);
            double mbakiye = BakiyeGetir(mno);
 
            if (mbakiye >= cekilen)
            {
                con.Open();
                string sorgu = "Update Hesap Set bakiye=(bakiye-@cekilen) where musterino=@musterino";
                cmd = new OleDbCommand(sorgu, con);
                cmd.Parameters.AddWithValue("@cekilen", cekilen);
                cmd.Parameters.AddWithValue("@musterino", Convert.ToInt32(textBox1.Text));
                cmd.ExecuteNonQuery();
                con.Close();
                Doldur();
            }
            else
            {
                MessageBox.Show("Yetersiz Bakiye. Şuanki Bakiyeniz: "+mbakiye.ToString("C2"));
            }
        }
    }
}