API class to connect with web php

Question

today I coded a simple API class in C# with just a WebClient instance in each void and just simple voids to do simple things, can anyone give me any support in how I can improove it? Thanks.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;

namespace uTune.Base.Api
{
    class API
    {
        /// <summary>
        /// Runs a website script vue a url.
        /// </summary>
        /// <param name="url">URL to run.</param>
        public void runScript(string url)
        {
            WebClient client = new WebClient();
            client.DownloadString(url);
        }

        /// <summary>
        /// Runs a website script with the option of multiple parameters
        /// </summary>
        /// <param name="url">URL to run.</param>
        /// <param name="parameters">A list of parameters to include.</param>
        public void runScriptWithParameters(string url, Dictionary<string, string> parameters)
        {
            string urlToRun = url;
            bool firstParam = true;

            if (parameters.Count > 0)
            {
                foreach (KeyValuePair<string, string> parameter in parameters)
                {
                    if (firstParam)
                    {
                        urlToRun += "?" + parameter.Key + "=" + parameter.Value;
                        firstParam = false;
                    }
                    else
                    {
                        urlToRun += "&" + parameter.Key + "=" + parameter.Value;
                    }
                }
            }

            runScript(urlToRun);
        }

        /// <summary>
        /// Returns the pages content after a script has been executed.
        /// </summary>
        /// <param name="url">URL to get the content from.</param>
        /// <returns>Webpages content.</returns>
        public string getScriptReturn(string url)
        {
            WebClient client = new WebClient();
            return client.DownloadString(url);
        }

        /// <summary>
        /// Returns the pages conect after a script has been executed.
        /// </summary>
        /// <param name="url">URL to get the content form.</param>
        /// <param name="parameters">Parameters included in the URL.</param>
        /// <returns>Webpages content</returns>
        public string getScriptReturnWithParameters(string url, Dictionary<string, string> parameters)
        {
            string urlToRun = url;
            bool firstParam = true;

            if (parameters.Count > 0)
            {
                foreach (KeyValuePair<string, string> parameter in parameters)
                {
                    if (firstParam)
                    {
                        urlToRun += "?" + parameter.Key + "=" + parameter.Value;
                        firstParam = false;
                    }
                    else
                    {
                        urlToRun += "&" + parameter.Key + "=" + parameter.Value;
                    }
                }
            }

            return getScriptReturn(urlToRun);
        }
    }
}

Answer 1

• both methods, runScriptWithParameters and getScriptReturnWithParameters have a lot of code in common which should be extracted to a separate method.
• using string concatenation by using += will create each time a new string because strings are immutable. A better way would be to use a StringBuilder instead.
• based on the .NET naming guidelines methods should be named using PascalCase casing.
• the check for if (parameters.Count > 0) is not needed, because if you get the enumerator and there are no items to enumerate over, the loops is just ending.
• you don't do any null validation on the methods parameters of your public methods. Omitting these will leak implementation details.
• you should use the var type whenever the type is obvious form the right hand of the assignment.

Implementing some of the mentioned points will lead to

private string ComposeUrlParameters(Dictionary<string, string> parameters)
{
    var builder = new StringBuilder(1024);
    var firstParameter = true;
    foreach (var parameter in parameters)
    {
        if (firstParameter)
        {
            builder.Append("?");
            firstParameter = false;
        }
        else
        {
            builder.Append("&");
        }
        builder.AppendFormat("{0}={1}",parameter.Key, parameter.Value);
    }

    return builder.ToString();
}  

which then can be called like so

public void RunScriptWithParameters(string url, Dictionary<string, string> parameters)
{
    if (url == null) { throw new ArgumentNullException("url"); }
    if (parameters == null) { throw new ArgumentNullException("parameters"); }  

    var urlToRun = url + ComposeUrlParameters(parameters);
    RunScript(urlToRun);
}

You could compose the url parameters with linq as well like so

private string ComposeUrlParameters(Dictionary<string, string> parameters)
{
    if (parameters.Count == 0)
    {
        return string.Empty;
    }

    var builder = new StringBuilder(1024);
    var firstParameter = parameters.First();

    builder.AppendFormat("?{0}={1}",firstParameter.Key, firstParameter.Value);

    foreach (var parameter in parameters.Skip(1)
    {
        builder.AppendFormat("&{0}={1}",parameter.Key, parameter.Value);
    }

    return builder.ToString();
}