System.ArgumentException: Argument 'Start' must be greater than zero.

Question

Hi

 

Any one pls help me

 Error: System.ArgumentException: Argument 'Start' must be greater than zero.

Dim binData As Byte()
        Dim counter As Integer
        Dim postedData As Integer
        'Dim dat As String
        'Dim fs As StreamWriter

        Server.ScriptTimeout = 18000000
        binData = Request.BinaryRead(Request.TotalBytes)
        ' Convert the binary data to ASCII
        'For counter = 1 To binData.Length
            postedData = postedData & Chr(Asc(Mid(binData.ToString(), counter, 1)))--Error System.ArgumentException: Argument 'Start' must be greater than zero.
       ' Next
        Dim datetime1 As String = DateTime.Now.ToString.Replace(" ", "")
        datetime1 = DateTime.Now.ToString.Replace(":", "")
        datetime1 = datetime1.ToString.Replace("/", "")
        datetime1 = datetime1.ToString.Replace("-", "")
        Dim sw As StreamWriter = File.CreateText("c:\Temparory\" & datetime1 & ".txt")
        'dat = Replace(Now(), " ", "")
        'dat = Replace(dat, ":", "")
        'dat = Replace(dat, "/", "")
        'fs = File.CreateText("c:\temp\" & dat.Now & ".txt")
        sw.Write(postedData)
        'For counter = 1 To binData.Length

        '    sw.Write(Convert.ToChar(binData(counter)))
        'Next
        sw.Close()
        sw = Nothing

 

 

Pls help,,,its very urgent

 

thanks in advance

Answer 1

Hi Suresh..,

I am so sorry that your problem wasn’t solved immediately.

As we all know that, the Function of Mid is to return a string containing a specified number of characters from a string. The declaration of Mid is as below:

Code Snippet

Mid is Public Shared Function Mid(

  ByVal str As String, _

  ByVal Start As Integer, _

   Optional ByVal Length As Integer _

) As String

 

 

If Start<=0 or Length<0, ArgumentException will occur. The value of counter is zero when the program runs to "postData=postData&....." Statement for it wan't assigned a value manually. Obviously we can see where the problem is.

 

Best Regards,

Bruce Zhou

Answer 2

binData.ToString() does not do what you expect it to do.  For example:

    Dim binData As Byte() = {1, 2, 3, 4}
    Console.WriteLine(binData.ToString())

output: System.Byte[]

You should do it this way:

    Dim postedData As String
    postedData = System.Text.Encoding.ASCII.GetString(binData)

Note that postedData must be a string, not an integer.