quick Q about ASCII

Hi

im trying to see if the current character is between 2 values in the ASCII table (numeric). if they are then I wish to continue. It works except when you enter a value of less than the ASCII value of 57 it assumes that it's true when it really isnt

how can i tell it to see if the value entered is between the numbers in the ASCII table?

Code:

---

foreach(char curChar in txtPortNumber.Text)
                                {
                                        //is it a number?
                                        if (curChar >= 48 && curChar <= 57 == false )
                                        {
                                                MessageBox.Show("Text entered is not numeric");
                                                return false;
                                        }
                                        else
                                        {
                                                fullString += curChar;
                                                if (Convert.ToInt32(fullString) > 65535)
                                                {
                                                        MessageBox.Show("Ports cannot be greater than 65535");
                                                        return false;                                                       
                                                }
                                        }
                                }

---

Get rid of this bit:" == false". These two expressions: "curChar >= 48" and "curChar <= 57" already evaluate to boolean values so there is no need to compare either or both of them to a boolean literal. Anyway, why not use Double.TryParse to check whether a string represents a numeric value.

thanks, ill try that too but found another way and seems to work fine :)

Code:

---

double tmpPrtNo;

if (!double.TryParse(txtPortNumber.Text, System.Globalization.NumberStyles.Integer, null, tmpPrtNo))
{
        MessageBox.Show("Text entered is not numeric");
        return false;
}


if(tmpPrtNo > 65535)
{
        MessageBox.Show("Ports cannot be greater than 65535");
        return false;
}

int portNumber = Convert.ToInt32(tmpPrtNo);

---

You might also consider using a NumericUpDown control with a Maximum of 65535 so vaildation is not necessary.

char.IsDigit(curChar);


:lol:

lol hehe
dunno whats going on, but as mentioned above, I would "strongly" suggest usign Double.TryParse if you're just trying to see if a string is a number