add,save,delete,find operations with datagridview

Introduction

After a long search and paining eyes, i myself tried to workout the manipulations like add,delete,save,find operations with datagridview in VB.NET through which a master data and details data are connected.

Background

Using the code

In the VB.NET - New Windows Forms:
Place 3 textboxes ,6 buttons, 1 datagridview
6 buttons are for :
new, save, clear, find, add row(for datagridview purpose), delete row.

Import the necessary things for the database connection and operations before the public class form1 line. I use PostGres here mainly for the purpose that it have the serial datatype which is very useful for autoincrement of any field. Moreover i use primary key for the tables.

In the database create 2 tables as below.
TABLE STRUCTURE IN DATABASE

1st table:

GBDEVEL=# \d test1;
Table "erp.test1"
Column | Type | Modifiers
-------- +----------------------- +-----------
eno | integer | not null -- primarykey
ename | character varying(10) |
salary | integer |
Indexes:
"test1_pkey" PRIMARY KEY, btree (eno)

use serial datatype if you are using postgres.

2nd table:


GBDEVEL=# \d test2;
Table "erp.test2"
Column | Type | Modifiers
-------- +--------- +-----------
enum | integer | -- foreign key
basic | integer |
hra | integer |

Foreign-key constraints:
"fk_t1" FOREIGN KEY (enum) REFERENCES test1(eno)

This article provides you that storing the data in the textboxes and in the datagridview in the database at 2 different tables, which are referred by foreignkey through primarykey. For Example, the particular eno will have the different basic,hra pack. May get confused...!!! Ok go further.

Imports Npgsql

Imports System.Data.SqlClient

Imports NpgsqlTypes

Imports System.Windows.Forms

Public Class Form1

Dim con As NpgsqlConnection

Dim NpgDA, NpgDA1 As NpgsqlDataAdapter

Dim ds As DataSet

Dim drow, drow1 As DataRow

Dim scb, scb1 As NpgsqlCommandBuilder

Dim cmd As NpgsqlCommand

Dim sdr As NpgsqlDataReader

Private Sub btnAddrow_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAddrow.Click

Dim item As New DataGridViewRow

DataGridView1.AllowUserToAddRows = True

item.CreateCells(DataGridView1)

End Sub

Private Sub btnDelRow_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDelRow.Click

For Each rows As DataGridViewRow In DataGridView1.SelectedRows

DataGridView1.Rows.Remove(rows)

Next

End Sub

Private Sub DataGridView1_CellEndEdit(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellEndEdit

DataGridView1.AllowUserToAddRows = False

End Sub

Private Sub btnNew_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNew.Click

TextBox1.Text = ""

TextBox2.Text = ""

TextBox3.Text = ""

DataGridView1.Rows.Clear()

End Sub

Private Sub btnClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClear.Click

TextBox1.Text = ""

TextBox2.Text = ""

TextBox3.Text = ""

DataGridView1.Rows.Clear()

End Sub

Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click

Dim col1 As String

Dim col2 As String

Dim i As Integer

'trans = con.BeginTransaction

NpgDA = New NpgsqlDataAdapter("select * from test1", con)

NpgDA1 = New NpgsqlDataAdapter("select * from test2", con)

scb = New NpgsqlCommandBuilder(NpgDA)

scb1 = New NpgsqlCommandBuilder(NpgDA1)

ds = New DataSet

NpgDA.Fill(ds, "test1")

NpgDA1.Fill(ds, "test2")

'DataGridView1.DataSource = ds.Tables(1)

drow = ds.Tables(0).NewRow

'   drow1 = ds.Tables(1).NewRow

drow(0) = TextBox1.Text

drow(1) = TextBox2.Text

drow(2) = TextBox3.Text

For i = 0 To DataGridView1.Rows.Count - 1

drow1 = ds.Tables(1).NewRow

col1 = DataGridView1.Rows.Item(i).Cells(0).Value

col2 = DataGridView1.Rows.Item(i).Cells(1).Value

drow1(1) = col1

drow1(2) = col2

ds.Tables(1).Rows.Add(drow1)

NpgDA1.Update(ds, "test2")

Next

ds.Tables(0).Rows.Add(drow)

NpgDA.Update(ds, "test1")

'  trans.Commit()

MsgBox("Data Added", MsgBoxStyle.Information)

End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

con = New NpgsqlConnection("Server=10.3.2.1;User Id=erp;Password=erp;Database=GBDEVEL")

con.Open()

End Sub

Private Sub btnFind_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnFind.Click

Dim s As String

Dim scm As New NpgsqlCommand

s = "select * from test1 where eno=" & TextBox1.Text & ""

scm = New NpgsqlCommand(s, con)

sdr = scm.ExecuteReader

If sdr.Read = True Then

TextBox2.Text = sdr(1).ToString

TextBox3.Text = sdr(2).ToString

Else

MsgBox("No such record")

End If

sdr.Close()

scm.Cancel()

End Sub

End Class

Type the Empno in the textbox1 and click find will produce the ename and salary.

i know many changes and updations, clear explanations to be done. Sure, i'll do it soon.

Points of Interest

saving the rows of datagridview for a particular eno and looping operations, i got very much confused and irritated many times. Don't forget to use primary keys. In MSSQL you have to write procedure for autoincrement of eno.

BEST OF LUCK!

History

TO BE UPDATED. PLS WAIT FOR MORE ENJOYMENT!!!! :) :)

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