Question

I’m writing an API and would like people to be able to supply a Google Charts API call as an argument. What’s the proper way to deconstruct this problematic API call, where an argument contains an entirely separate API call?

For instance:

?method=createimage&chart1=https://chart.googleapis.com/chart?chs=250x100&chd=t:60,40&cht=p3&chl=Hello|World

In the example above, I’d like to think of it as (2) query string keys: method and chart1. Is it possible for me to parse the above example as 2 query string keys, leaving the Google Charts API call intact, rather than breaking it down? Could I enclose the call as JSON or something along those lines?

Thanks much! Cheers

Answer 1

Here’s the proper way (using the ParseQueryString method):

using System;
using System.Web;

class Program
{
    static void Main()
    {
        var query = "?method=createimage&chart1=https://chart.googleapis.com/chart?chs=250x100&chd=t:60,40&cht=p3&chl=Hello|World";
        var values = HttpUtility.ParseQueryString(query);
        Console.WriteLine(values["method"]);
        Console.WriteLine(values["chart1"]);
    }
}

and if you wanted to construct this query string:

using System;
using System.Web;

class Program
{
    static void Main()
    {
        var values = HttpUtility.ParseQueryString(string.Empty);
        values["method"] = "createimage";
        values["chart1"] = "https://chart.googleapis.com/chart?chs=250x100&chd=t:60,40&cht=p3&chl=Hello|World";
        Console.WriteLine(values);
        // prints "method=createimage&chart1=https%3a%2f%2fchart.googleapis.com%2fchart%3fchs%3d250x100%26chd%3dt%3a60%2c40%26cht%3dp3%26chl%3dHello%7cWorld"
    }
}

Oh and by the way, what you have shown in your question is an invalid query string which is confirmed by the output of the second code snippet I have shown. You should URL encode your chart1 parameter. It’s absolutely against all standards to have more than one ? character in a query string.

Here’s how the correct query string would look like:

?method=createimage&chart1=https%3A%2F%2Fchart.googleapis.com%2Fchart%3Fchs%3D250x100%26chd%3Dt%3A60%2C40%26cht%3Dp3%26chl%3DHello%7CWorld