Visual C# problem, SerialPort DataReceive

Gary Soh

Hello,

I am trying to translate my Visual Basic program to C#.
Right now i am have having problems translating this code

[CODE]Private Sub SerialPort1_DataReceived(ByVal sender As System.Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived

inchar = SerialPort1.ReadLine
IDstr = Microsoft.VisualBasic.Left(inchar, 2)
Datastr = Microsoft.VisualBasic.Right(inchar, 6)

result = Val("&h" & Datastr)
''Energy = (result * 38) / 1000

End Sub[/CODE]

I'd like to know how to make my IDstr read the most left 2 bits, and Datastr read the right most 6 bits.

For now i have this:
[CODE]private void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
{
string inchar, IDstr, Datastr;
inchar = SerialPort1.ReadLine();
IDstr = Microsoft.VisualBasic.Left(inchar, 2); // need help translating this line
Datastr = Microsoft.VisualBasic.Right(inchar, 6); // need help translating this line

result = Val("&h" & Datastr);
/*''Energy = (result * 38) / 1000;*/
}[/CODE]

Thank you!

5 Replies

Know the answer? Post it — somebody with the same question will find it here.

Vulpes15y ago
In that case 'result' must be an int rather than a uint (can't remember now why I thought it was), so just use:

result = Convert.ToInt32(Datastr, 16);

Incidentally, you're opening post - when you were talking about 'bits' - sounded like you were expecting a binary rather than a hexadecimal string?

If that's the case, then change '16' in the above line to '2'.
Gary Soh15y ago
private void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
        {
            string inchar = string.Empty;
            string IDstr = string.Empty;
            string Datastr = string.Empty;
            int result ;

            inchar = SerialPort1.ReadLine();

            IDstr = inchar.Substring(0, 2);
            Datastr = inchar.Substring(inchar.Length - 6);

            result = Convert.ToUInt32(Datastr, 16);

            /*''Energy = (result * 38) / 1000;*/
        }

there an new error on that line after replacing it.
"cannot implicitly convert type 'uint' to 'int'. An explicit conversion exists(are you missing a cast?)
Vulpes15y ago
This line is wrong:

Datastr = inchar.Substring(inchar.Length - 7);

and should be:

Datastr = inchar.Substring(inchar.Length - 6);

That's because C# uses zero-based indexing for strings. The last character is therefore at an index of inchar.Length - 1 and the 6th last character at inchar.Length - 6.

Notice also that if a string with a length of less than 6 is received from the SerialPort, you'll get an exception.

Val takes DataStr, treats it as a hex string by prepending "&h" and converts it to an integer.

If result is a UInt32, then I'd use:

result = Convert.ToUInt32(Datastr, 16);
Gary Soh15y ago
After some researching i have this:

private void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
{
string inchar = string.Empty;
string IDstr = string.Empty;
string Datastr = string.Empty;
Int32 result;

inchar = SerialPort1.ReadLine();

IDstr = inchar.Substring(0, 2);
Datastr = inchar.Substring(inchar.Length - 7);

result = Val("&h" & Datastr);

/*''Energy = (result * 38) / 1000;*/
}

about the result = Val("&h" & Datastr);
I have a problem with Val, how do i fix it?
Vulpes15y ago
In C#, those last three lines would translate to:

int len = inchar.Length;

if (len >= 2)
IDstr = inchar.Substring(0,2);
else
IDstr = inchar;

if (len >= 6)
Datastr = inchar.Substring(len - 6);
else
Datastr = inchar;

// 'result' assumed to be an int defined elsewhere
result = Convert.ToInt32(Datastr, 16);