Category: quiz

Some code

What you do not like about this code ? ( I have found 3 things – how many can you find?)

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public static MyNewDocument  OpenDocument(string FileDocPath , out int codeError)
{
 
    if (string.IsNullOrEmpty(FileDocPath) || !File.Exists(FileDocPath))
    {
            codeError = 1;
            return null;
    }
 
    MyNewDocument doc = null;
    try
    {
              doc = new MyNewDocument(FileDocPath);
              if (doc == null)
                    throw new Exception();
              codeError = 0;
              return doc;
     }
     catch
    {
              codeError = 2;
              return null;
    }
 
}

path.combine idiosyncrasies

I have this small program :

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var s = Path.Combine(@"E:\andrei", UnknownVar);
Console.WriteLine(Directory.GetFiles(s).FirstOrDefault());

In what conditions , if I have an “C:\andrei” folder with a single file , the output will be the name of the file ?
And where you want to be aware of this behaviour ?
Hint : The output is : \andrei\New Text Document.txt

Find the Error

This code was written by me, in a late night moment, when copy paste seems the best option
It started this way :

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public string ImportFeed(string URL)
        {
            string ret = "";
            XmlDocument xd = new XmlDocument();
            xd.Load(URL);           
            for(int i=0;i<xd.ChildNodes.Count;i++)
            {
                ret += xd.ChildNodes[i].Name;
            }
            return ret;
             
        }

So far , nothing special. Just open the url, read into an XML , return first nodes. Then I wanted more – next nodes. Nothing easier – why bother with recursion or proper variable names ? Just copy and paste :

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public string ImportFeed(string URL)
        {
            string ret = "";
            XmlDocument xd = new XmlDocument();
            xd.Load(URL);           
            for(int i=0;i<xd.ChildNodes.Count;i++)
            {
                ret += xd.ChildNodes[i].Name;
                for (int j = 0; i < xd.ChildNodes[i].ChildNodes.Count; j++)
                {
                    ret += xd.ChildNodes[i].ChildNodes[j].Name;
                }
            }
            return ret;
             
        }

Could you spot the error ?
Hint : I have discovered after 10 seconds …but not looking at the code…

C# quiz

Fast small quiz for sunny afternoon :
What is writing at the console those lines : ( please do not use a compiler) :

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decimal? v = 100;
Console.WriteLine(v);
decimal? x = null;
x += v.Value;
Console.WriteLine(x);

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