object reference not set to an instance of an object for registry key code

[mohammed saleh]

Dim key As RegistryKey = Registry.LocalMachine.OpenSubKey("Software\CATS\Conn")

    Dim DS As Object = key.GetValue("DataSource")->(Error) "object referenc not set to inestance of an object"(/Error) 
    Dim DB As Object = key.GetValue("DataBase")
    Dim Uid As Object = key.GetValue("UserName")
    Dim Pass As Object = EncDecCls.EncryptClass.DecryptTripleDES(key.GetValue("Password"))
 Dim con As New SqlConnection( _
      "Data Source =" & DS & ";" & _
    "Database =" & DB & ";" & _
" User id =" & Uid & "; Password =" & Pass & ";")

please help me

[r035198x]

1.) Use code tags when posting code.

2.) So the registry key you looked up was not found. Check that it really does exist or it's accessible or you are using the correct name format to access it.

[VanessaMeacham]

HI ! I agree with r035198x. Please Check it.

[mohammed saleh]

I checked the name
but show this error

my data source(server name) is (local)
database moh

are registrykey accept the server name (local)

[vijay6]

Hey mohammed saleh, you're getting this error because inside the 'HKEY_LOCAL_MAC HINE -> Software -> CATS -> Conn' directory 'DataSource' key doesn't exists (r035198x answer is right).

Before reading the key's value in Registry first you've to check whether that key is already exists or not.

You can check whether the key is already present or not in registry using the following code,

bool found = false;

RegistryKey rs1 = Registry.LocalMachine;
RegistryKey rs2 = rs1.OpenSubKey("SOFTWARE\\CATS\\Conn");

string[] allkeynames = rs2.GetValueNames();
            
foreach(var temp in allkeynames)
{
if (temp.Equals("DataSource"))
{
found = true;
break;
}
}
if(found)
Console.WriteLine("Key exists");
else
Console.WriteLine("Key doesn't exists");

[mohammed saleh]

This problem is solved

I used Text File connection string


The answer:

 Public Function Readconnectionstring() As String
        Try

            Dim pass As String = ""
            Dim path As String = "C:\connection\Textfile.txt"
            Dim sw As StreamWriter = New StreamWriter(path)
            sw.WriteLine()
            EncDecCls.EncryptClass.EncryptTripleDES(pass)


            Dim sr As StreamReader = New StreamReader(path)
            Dim line As String = sr.ReadLine()

           

            Dim ds As String = sr.ReadLine()
            Dim db As String = sr.ReadLine()
            Dim uid As String = sr.ReadLine()
            pass = EncDecCls.EncryptClass.EncryptTripleDES(sr.ReadLine())


            cons = "Data Source = " & ds & "; DataBase =" & db & "; User Id =" & uid & "; Password =" & pass & ";"
        Catch ex As FileNotFoundException
            MsgBox(ex.Message)
        End Try
        Return cons
    End Function