Resistor color code

[Pavlex4]

How to convert C++ to C# ?

[Pavlex4]

How to make support for 5 band and 6 band resistor and how to make support for mΩ,uΩ,nΩ,pΩ ?
What should I add?

[2kaud]

How to make support for 5 band and 6 band resistor and how to make support for mΩ,uΩ,nΩ,pΩ ?
What should I add?

This is going to be up to you. I very much doubt that any forum member will provide this - and I'm not going to. As I indicated in previous posts, the code I posted was a basic starter to demonstrate some concepts as to one way in which the problem could be approached - and by no means the only way. You are free to use this code as required. Your original question was to help you to make an app that converts resistance to colour - not write the whole program! I provided the code as c++ as I don't program using c# - but if you are a programmer then it shouldn't require much work to to be able to understand how the c++ program works and to apply its methods to c#.

make an app

For what type of device is this app intended for?

[Pavlex4]

For Windows.I translated code and I it works fine.

[Pavlex4]

What this part of code means:
Color.FromName(colours[res[0] - '0']);
Color.FromName(colours[res[1] - '0']);
Color.FromName(colours[third != 0 ? third : res.Count() - 2]);

[2kaud]

colours is an array with an index that starts at 0. res is a string representation of the value. res[0] is the first char in the string (the left char) So if res has the value 4700 then res[0] is the char 4 and res[1] is the char 7. But colours requires an index starting at 0, so subtracting '0' from the char value gives a number starting at 0 (id res[0] is '0' then subtracting '0' gives 0) that can be used to index into colours array to obtain the colour name.

third != 0 ? third : res.Count() - 2]

This is effectively the same as

if (third != 0)
   colours[third];
else
   colours[res.Count() - 2];

So if the value of third has been set, then use this value as a direct element index into colours. If it has not been set then find the number of digits to the right of the first two. This will give the value of the third band as the multiplier. .Count() provides the number of chars in the string res so subtract 2 to ignore the first 2 and then use this value as the index into colours to get the required colour for the multiplier band.

[Pavlex4]

Do I just need to add something below this:
Color.FromName(colours[res[0] - '0']);
Color.FromName(colours[res[1] - '0']);
Color.FromName(colours[third != 0 ? third : res.Count() - 2]);

[2kaud]

For c# ????? As I've previously said, I don't program using c#. Perhaps a c# guru could help?

[Pavlex4]

For C++?

[Pavlex4]

Can it be done like this:
label15.BackColor = Color.FromName(colours[res[0] - '0']);
label16.BackColor = Color.FromName(colours[res[1] - '0']);
label17.BackColor = Color.FromName(colours[res[2] - '0']);
label18.BackColor = Color.FromName(colours[third != 0 ? third : res.Count() - 3]);

[2kaud]

For 5 band? No. That would also require changes in other parts of the program.

[Pavlex4]

I tested 5 and 6 band and it's working good!!!

[Pavlex4]

mΩ is working good but I have problem with uΩ,nΩ,pΩ !!!
https://postimg.org/image/y6q4bw64d/

[2kaud]

As the issue is out of range with res[1] in line 136, the string res only has one char so trying to access the second char is causing the error. Therefore val has a value that is less than 10. For that line to work, val has to have a value of 10 or greater. In my original c++ code, there was code to ensure this.

PS Same goes for the code in post #25 where you are accessing res[2]. For that to work, val must have a value of at least 100 - other the same issue with out of range will occur.

[Pavlex4]

I have that code:

if (isUnitCorrect && isValueCorrect)
                {
                    double mul = factorDictionary[lastChar];
                    double val = double.Parse(value) * mul;
                    int third = 0;

                    if (val < 1)
                    {
                        val *= 100;
                        third = 9;
                    }
                    else if (val < 10)
                    {
                        val *= 10;
                        third = 10;
                    }

                    res = val.ToString();

                    if (res.Count() > 24)
                        MessageBox.Show("Invalid value");

                    else
                    {
                        label15.BackColor = Color.FromName(colours[res[0] - '0']);
                        label16.BackColor = Color.FromName(colours[res[1] - '0']);
                        label17.BackColor = Color.FromName(colours[third != 0 ? third : res.Count() - 2]);
                    }