Manage complex string array in C#

Question

I want to use a string array stored in the web.config to easily change its values, this is in the format: full_w=670|small_w=100,q=low|tiny_h=30,c=true. Each template is split by the | (pipe) and then each of those sets comprises of a name (left of _) and its corresponding values (right of _), the values can be several and each separated by the , (comma). I think this possibly qualifies for a 3D array, I just can't seem to get an easy way to read this in a sensible manner. Any ideas or solutions as to the best way to read/manage the data from this string?

Basically, in the end I want to be able to call the template small and read its values which in this case are width=100 and quality=low.

Answer 1

Here's the function I wrote to parse one of these settings strings:

public static Dictionary<string, Dictionary<string, string>> getSettings(string settingsStr)
{
    return settingsStr.Split('|').ToDictionary(
        template => template.Split('_')[0],
        template => template.Split('_')[1].Split(',').ToDictionary(
            setting => setting.Split('=')[0],
            setting => setting.Split('=')[1]));
}

It just uses a lot of string .Splitting and .ToDictionarying.

Here's the test, showing that it works:

var result = getSettings("full_w=670|small_w=100,q=low|tiny_h=30,c=true");
/*
result = {
    [ "full" => [ "w" => "670" ] ]
    [ "small" => [ "w" => "100", "q" => "low" ] ]
    [ "tiny" => [ "h" => "30", "c" => "true" ] ]
}
*/

To read the values w and q from template small, you can do this:

int width = int.Parse(result["small"]["w"]);
string quality = result["small"]["q"];

Edit: As an added bonus, if you want to convert the Dictionary<string, Dictionary<string, string>> back into a single settings sting, you can use this method:

public static string getSettingsStr(Dictionary<string, Dictionary<string, string>> settings)
{
    return string.Join("|",
        settings.Select(kvp =>
            kvp.Key + "_" + string.Join(",",
                kvp.Value.Select(setting =>
                    setting.Key + "=" + setting.Value))));
}

Use:

string settingsStr = getSettingsStr(result);
// settingsStr = "full_w=670|small_w=100,q=low|tiny_h=30,c=true"

If you want to check that a specific template or setting exists, then use the .ContainsKey() method:

// If I have "Dictionary<string, Dictionary<string, string>> settings;"
int width = -1;
string quality = null;
if (settings.ContainsKey("small"))
{
    if (settings["small"].ContainsKey("w"))
        width = int.Parse(settings["small"]["w"]);
    if (settings["small"].ContainsKey("q"))
        quality = settings["small"]["q"];
}

Answer 2

Have you considered using plain old XML Serialization with your own plain old C# objects. Here is an example:

public class Program
{
    static void Main(string[] args)
    {
        var data = new MyConfig[2];

        for (int i = 0; i < 2; i++)
        {
            data[i] = new MyConfig { Name = "Name" + i };

            data[i].Properties = new MyConfigAttribute[]
            {
                new MyConfigAttribute { Name = "Property Name " + i, Value = "Property Value " + i },
                new MyConfigAttribute { Name = "2nd Property Name " + i, Value = "2nd Property Value " + i },
            };
        }

        var serializer = new XmlSerializer(typeof(MyConfig[]));
        using (StreamWriter tw = File.CreateText(@"c:\temp\myconfig.xml"))
        {
            serializer.Serialize(tw, data);
        }

        using (StreamReader tw = File.OpenText(@"c:\temp\myconfig.xml"))
        {
            var readBack = serializer.Deserialize(tw);
        }


        Console.ReadLine();
    }

    [XmlRoot("MY_CONFIG")]
    public class MyConfig
    {
        [XmlElement("NAME")]
        public string Name { get; set; }

        [XmlArray]
        [XmlArrayItem(typeof(MyConfigAttribute))]
        public MyConfigAttribute[] Properties { get; set; }
    }

    [XmlRoot("MY_CONFIG_ATTRIBUTE")]
    public class MyConfigAttribute
    {
        [XmlElement("ATTRIBUTE_NAME")]
        public string Name { get; set; }

        [XmlElement("ATTRIBUTE_VALUE")]
        public string Value { get; set; }
    }
}

Basically, you create a class to store your individual attributes (MyConfigAttribute in this case), wrap it in another class to provide your name for a group of related attributes (MyConfig in this case), then use normal XML Serialization to write the settings out to an individual XML file, like this section of the code

        var serializer = new XmlSerializer(typeof(MyConfig[]));
        using (StreamWriter tw = File.CreateText(@"c:\temp\myconfig.xml"))
        {
            serializer.Serialize(tw, data);
        }

You can read it back to objects again using this section of the code:

        using (StreamReader tw = File.OpenText(@"c:\temp\myconfig.xml"))
        {
            var readBack = serializer.Deserialize(tw);
        }

The advantage of this is:

• It is simple to understand and use
• You can add features to your custom class, e.g. to add values to the array of properties, thereby lending itself to wrapping a custom screen around it.

Look up C# XML Serialization on Google!