Convert method params string[] to Dictionary

Question

In some utility libraries I have methods that have a params[] parameter. In many of these cases, these end up as key/value pairs which would be even more useful if I could convert these to a dictionary.

What would be the most efficient method to do this? Can I do this via Linq somehow?

Here is an example:

public static Uri appendParams(Uri uri, params string[] parameters)
    {
        if (uri == null)
        {
            return null;
        }

        if (parameters == null) {
            return uri;
        }

        var queryStringBuilder = new StringBuilder(uri.Query ?? "");

        //Would like to convert the params[] argument to a dictionary here
        Dictionary<String, String> paramsDictionary = null; // Not sure best way to do this...

        foreach (KeyValuePair<String, String> kvp in paramsDictionary)
        {
            queryStringBuilder.Append(kvp.Key + "=" + kvp.Value);
        }

        var uriBuilder = new UriBuilder(uri);
        uriBuilder.Query = queryStringBuilder.ToString();

        return uriBuilder.Uri;
    }

Are the keys and values stored in a specific order inside the array? — Yuval Itzchakov, Nov 30 '14 at 06:04
Why don't you just specify a dictionary as the argument type, and let the client create it? — Rufus L, Nov 30 '14 at 06:04
@YuvalItzchakov arguments are passed in this order: key, value, key, value etc. — andersra, Nov 30 '14 at 06:08
@RufusL I thought about it, but then I took this approach and not able to come up with the proper method for this, so now I'm curious. — andersra, Nov 30 '14 at 06:09
So you don't allow a key without a value? i.e. no 'switch' params? And if a key is specified more than once, you only use the last specified value? — Rufus L, Nov 30 '14 at 06:13

score 0 · Answer 1 · answered Nov 30 '14 at 06:26

0

If you're building a string and using it right away (and not using the dictionary for anything else), then you can skip the dictionary creation step and just build your query string from the parameter array:

for (int i = 0; i < parameters.Length - 1; i += 2)
{
    var concatChar = (i == 0) ? "?" : "&";
    queryString.AppendFormat("{0}{1}={2}", 
        concatChar, parameters[i], parameters[i + 1]);
}

answered Nov 30 '14 at 06:26

Rufus L

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Ended up doing it without LINQ: – andersra Dec 01 '14 at 05:06

Convert method params string[] to Dictionary

1 Answers1