Getting little square characters instead of Text

[Madiha Ahmed]

I am sending SNMP SystemName query to local host and in response i m getting little square characters instead of the specific system name..

Imports System.Text
 
Class Form1
 
    Dim commlength As Integer, miblength As Integer, datatype As Integer, datalength As Integer, datastart As Integer
    Dim uptime As Integer
    Dim output As String
    Dim conn As New SNMP()
    Dim response As Byte() = New Byte(1023) {}
    'Public Shared Sub Main(ByVal argv As String())
    'End Sub

 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        IPaddress.Text = "115.186.115.188"
        Community.Text = "public"
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
 
        ListBox1.Items.Add("Device SNMP information:")
 
        ' Send sysName SNMP request
        response = conn.[get]("get", IPaddress.Text, Community.Text, "1.3.6.1.2.1.1.5.0")
        If response(0) = &HFF Then
            ListBox1.Items.Add("No response from " & IPaddress.Text)
            Return
        End If
 
        ' If response, get the community name and MIB lengths
        commlength = Convert.ToInt16(response(6))
        miblength = Convert.ToInt16(response(23 + commlength))
 
        ' Extract the MIB data from the SNMP response
        datatype = Convert.ToInt16(response(24 + commlength + miblength))
        datalength = Convert.ToInt16(response(25 + commlength + miblength))
        datastart = 26 + commlength + miblength
        output = Encoding.ASCII.GetString(response, datastart, datalength)
        ListBox1.Items.Add("  sysName - Datatype:" & datatype & "," & output)

And this is the output m getting

Device SNMP Information:

sysName - Datatype: 48, [][][][]

[Rabbit]

I don't know what SNMP is but are you sure the data is ASCII encoded? Those square boxes that are displayed are usually because the data contains undisplayable characters. This means one of two things, either it uses a different character encoding scheme or the data is binary. In the former case, you will have to use the correct encoding. In the latter case, you should display it as hex.