hi all ... i am designing a software where i am using login and password. the user and password is store in notepad which is connected with listview . now i dont know i mean i need something when user enter user and password it should search and if details available in listview then goto form 2 else reject
something like
if textbox1.text=listview.items.find then
form2.show
end if
please help me i need urgent answer
To search you can use ListView1.Items.ContainsKey(key As String) function.
May I suggest a safer method of storing a password?
You could create a database in something as simple as access and store the passwords in a table.
To increase the security further, you can encrypt the passwords and store the encrypted string into the database.
This method is called trap door encryption.
(Example uses Microsoft's example found here)
(Example uses Access 2010 and Visual Studio 2010)
(Example connection code uses System.Data.OleDB)
For example:
Imports System.Security.Cryptography
Public Class Encryption
Private TripleDes As New TripleDESCryptoServiceProvider
Sub New(ByVal key As String)
' Initialize the crypto provider.
TripleDES.Key = TruncateHash(key, TripleDES.KeySize \ 8)
TripleDES.IV = TruncateHash("", TripleDES.BlockSize \ 8)
End Sub
Private Function TruncateHash( ByVal key As String, ByVal length As Integer) As Byte()
Dim sha1 As New SHA1CryptoServiceProvider
' Hash the key.
Dim keyBytes() As Byte =
System.Text.Encoding.Unicode.GetBytes(key)
Dim hash() As Byte = sha1.ComputeHash(keyBytes)
' Truncate or pad the hash.
ReDim Preserve hash(length - 1)
Return hash
End Function
Public Function EncryptData(ByVal plaintext As String) As String
' Convert the plaintext string to a byte array.
Dim plaintextBytes() As Byte =
System.Text.Encoding.Unicode.GetBytes(plaintext)
' Create the stream.
Dim ms As New System.IO.MemoryStream
' Create the encoder to write to the stream.
Dim encStream As New CryptoStream(ms,
TripleDes.CreateEncryptor(),
System.Security.Cryptography.CryptoStreamMode.Write)
' Use the crypto stream to write the byte array to the stream.
encStream.Write(plaintextBytes, 0, plaintextBytes.Length)
encStream.FlushFinalBlock()
' Convert the encrypted stream to a printable string.
Return Convert.ToBase64String(ms.ToArray)
End Function
Public Function DecryptData(ByVal encryptedtext As String) As String
' Convert the encrypted text string to a byte array.
Dim encryptedBytes() As Byte = Convert.FromBase64String(encryptedtext)
' Create the stream.
Dim ms As New System.IO.MemoryStream
' Create the decoder to write to the stream.
Dim decStream As New CryptoStream(ms,
TripleDes.CreateDecryptor(),
System.Security.Cryptography.CryptoStreamMode.Write)
' Use the crypto stream to write the byte array to the stream.
decStream.Write(encryptedBytes, 0, encryptedBytes.Length)
decStream.FlushFinalBlock()
' Convert the plaintext stream to a string.
Return System.Text.Encoding.Unicode.GetString(ms.ToArray)
End Function
End Class
And for the connection form:
Public Class myForm
Private Sub btnTestIt_Click(sender As System.Object, e As System.EventArgs) Handles btnTestIt.Click
'Encrypted value was inserted into the database beforehand.
Dim Crypt As New Encryption("MyTestKey")
Dim con As New OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;" & _
"Data Source=C:\myFolder\UserInfo.accdb;" & _
"Persist Security Info=False;")
Dim da As New OleDb.OleDbDataAdapter("SELECT Password FROM tblUserInfo WHERE UserName=?", con)
Dim ds As New DataSet
Try
da.SelectCommand.Parameters.AddWithValue("@UserName", txtUserName.Text)
da.Fill(ds, "UserInfo")
If Not IsNothing(ds.Tables("UserInfo")) Then
If ds.Tables("UserInfo").Rows.Count > 0 Then
If ds.Tables("UserInfo").Rows(0)("Password") = Crypt.EncryptData(txtPassword.Text) Then
MsgBox("You are authorized!", MsgBoxStyle.Information, "Hooray!")
Else
MsgBox("You are not authorized!", MsgBoxStyle.Exclamation, "Oh no!")
End If
Else
MsgBox("No rows were returned from table!", MsgBoxStyle.Exclamation, "Oops!")
End If
Else
MsgBox("User not found in table!", MsgBoxStyle.Exclamation, "Oops!")
End If
Catch ex As Exception
MsgBox(ex.Message, MsgBoxStyle.Critical, "Error!")
End Try
End Sub
End Class
Place this code in a test form and test it for yourself!
For my example I stored the following in the UserInfo table:
UserName:User1 Password:(EncrpytedUserPasswordString)
Please see the attached files for a better understanding.
thank you for your reply but i need simple code because i am not working on database. what i am doing is that i made a login and password.when user will enter password and username and press enter, it will retrive data from listview and if user exits it will allow user to enter.
LOGIN SCRREN CONNECTED TO LISTVIEW ...something like this...
or tell me who i can search items from listview column 1 and 2 and if record found the messagebox or label must tell "record found"
thanks in advance
Shark_1 ..i tried it
If ListView1.Items.ContainsKey(TextBox1.Text) Then
MsgBox(" done")
Else
MsgBox(" not found")
End If
but msgbox shows not found message. can you please write the code .
Followings should work.
Public Class Form1
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Dim lv As New ListViewItem
For i As Integer = 65 To 90
lv = ListView1.Items.Add(Chr(i), Chr(i), 0)
lv.SubItems.Add(i.ToString)
Next
End Sub
Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
If ListView1.Items.ContainsKey(Trim(TextBox1.Text)) = True Then
If ListView1.Items(TextBox1.Text).SubItems(1).Text = Trim(TextBox2.Text) Then
MessageBox.Show("Yes! I do.")
Else
MessageBox.Show("No! I don't.")
End If
Else
MessageBox.Show("No! I don't.")
End If
End Sub
End Class
Here Button1 to populate listview and button2 to search data on the value of Textbox1 and TextBox2. Assume the text of TextBOx1 as user and TextBox2 as password.
Dim boolFound As Boolean = False
Dim str As String = TextBox1.Text
Dim str1 As String = TextBox2.Text
For Each LvItem As ListViewItem In Me.ListView1.Items
If LvItem.SubItems(1).Text.Contains(str1) Then
boolFound = True
Label3.Text = "found"
Label2.Text = "Found"
selection.Show()
Exit For
End If
Next
If Not boolFound Then
MsgBox("Wrong User\Password", vbOKOnly + vbCritical, "Wrong User\Pass")
End If
i write above code which is working for me but it will search from one textbox. i have 2 textbox. 1st is for user and 2nd is for password. first is working fine but how i can add 2nd textbox i above code so it search itemsub 1 and itemsub 2
Shark_1 thanks alot for your last code it worked but it only searching the numbers not strings. my user and passwords depends on strings like
username = "admin"
password = "admin"
but it not searching it. if i seach 1 2 3 .... then it work or only for a b c d it working but not for complete word
You can do it like
Imports System
Imports System.Globalization
Public Class Form1
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Dim lv As New ListViewItem
For i As Integer = 65 To 90
lv = ListView1.Items.Add(Chr(i) & Chr(i + 32) & Chr(i), Chr(i) & Chr(i + 32) & Chr(i), 0)
lv.SubItems.Add(Chr(i + 32) & Chr(i + 32) & Chr(i + 32))
Next
End Sub
Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
Dim MatchResult As Boolean = False
For Each lv As ListViewItem In ListView1.Items
If String.Compare(lv.Text, TextBox1.Text, False, CultureInfo.CurrentCulture) = 0 Then
If String.Compare(lv.SubItems(1).Text.Trim, TextBox2.Text.Trim, False, CultureInfo.CurrentCulture) = 0 Then
MessageBox.Show("Yes! I do.")
ListView1.Focus()
'lv.Focused = True
lv.Selected = True
lv.EnsureVisible()
MatchResult = True
Exit For
Else
MatchResult = False
End If
Else
MatchResult = False
End If
Next
If Not MatchResult Then
MessageBox.Show("No! I don't.")
End If
End Sub
End Class
thankssssssssssssss it worked
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