How can I send an array as a query string parameter in C #?

Question

I am trying to use the home web API to retrieve some data. The documentation is written in PHP. The example I'm looking at is this:

$params = array( 'id' => 1 ,'data' => array( ,'email' => ' [e-mail] ' ) $url = "www.someapi.com/api?" . http_build_query( $params ); 

I am using the C # WebClient class, but I cannot figure out how to serialize the data parameter:

 WebClient wc = new WebClient(); wc.QueryString["id"] = "1"; wc.QueryString["data"] = // I have no idea. string json = wc.DownloadString(apiUrl); 

I tried several options:

 wc.QueryString["data"] = " email=[e-mail] "; wc.QueryString["data"] = Uri.EscapeDataString("data[email] =[e-mail] "); wc.QueryString["data"] = Uri.EscapeDataString("email[0] =[e-mail] "); wc.QueryString["data"] = Uri.EscapeDataString(" email=[e-mail] "); 

Of course, I don't have PHP settings anywhere to see exactly how http_build_query () returns.

Answer 1

I finally figured it out. I guess posting this question has reloaded my brain.

This is what worked:

 wc.QueryString["data[email]"] = " [e-mail] "; 

Answer 2

Notice this question is very important for this answer, so I put this class as the answer there . This answer will receive any updates for this class.

As far as I know, nothing has been created for this. But you can create your own class.

So I did:

 /// <summary> /// Helps up build a query string by converting an object into a set of named-values and making a /// query string out of it. /// </summary> public class QueryStringBuilder { private readonly List<KeyValuePair<string, object>> _keyValuePairs = new List<KeyValuePair<string, object>>(); /// <summary> Builds the query string from the given instance. </summary> public static string BuildQueryString(object queryData, string argSeperator = "&") { var encoder = new QueryStringBuilder(); encoder.AddEntry(null, queryData, allowObjects: true); return encoder.GetUriString(argSeperator); } /// <summary> /// Convert the key-value pairs that we've collected into an actual query string. /// </summary> private string GetUriString(string argSeperator) { return String.Join(argSeperator, _keyValuePairs.Select(kvp => { var key = Uri.EscapeDataString(kvp.Key); var value = Uri.EscapeDataString(kvp.Value.ToString()); return $"{key}={value}"; })); } /// <summary> Adds a single entry to the collection. </summary> /// <param name="prefix"> The prefix to use when generating the key of the entry. Can be null. </param> /// <param name="instance"> The instance to add. /// /// - If the instance is a dictionary, the entries determine the key and values. /// - If the instance is a collection, the keys will be the index of the entries, and the value /// will be each item in the collection. /// - If allowObjects is true, then the object properties' names will be the keys, and the /// values of the properties will be the values. /// - Otherwise the instance is added with the given prefix to the collection of items. </param> /// <param name="allowObjects"> true to add the properties of the given instance (if the object is /// not a collection or dictionary), false to add the object as a key-value pair. </param> private void AddEntry(string prefix, object instance, bool allowObjects) { var dictionary = instance as IDictionary; var collection = instance as ICollection; if (dictionary != null) { Add(prefix, GetDictionaryAdapter(dictionary)); } else if (collection != null) { Add(prefix, GetArrayAdapter(collection)); } else if (allowObjects) { Add(prefix, GetObjectAdapter(instance)); } else { _keyValuePairs.Add(new KeyValuePair<string, object>(prefix, instance)); } } /// <summary> Adds the given collection of entries. </summary> private void Add(string prefix, IEnumerable<Entry> datas) { foreach (var item in datas) { var newPrefix = String.IsNullOrEmpty(prefix) ? item.Key : $"{prefix}[{item.Key}]"; AddEntry(newPrefix, item.Value, allowObjects: false); } } private struct Entry { public string Key; public object Value; } /// <summary> /// Returns a collection of entries that represent the properties on the object. /// </summary> private IEnumerable<Entry> GetObjectAdapter(object data) { var properties = data.GetType().GetProperties(); foreach (var property in properties) { yield return new Entry() { Key = property.Name, Value = property.GetValue(data) }; } } /// <summary> /// Returns a collection of entries that represent items in the collection. /// </summary> private IEnumerable<Entry> GetArrayAdapter(ICollection collection) { int i = 0; foreach (var item in collection) { yield return new Entry() { Key = i.ToString(), Value = item, }; i++; } } /// <summary> /// Returns a collection of entries that represent items in the dictionary. /// </summary> private IEnumerable<Entry> GetDictionaryAdapter(IDictionary collection) { foreach (DictionaryEntry item in collection) { yield return new Entry() { Key = item.Key.ToString(), Value = item.Value, }; } } } 

Same:

 // Age=19&Name=John%26Doe&Values%5B0%5D=1&Values%5B1%5D=2&Values%5B2%5D%5Bkey1%5D=value1&Values%5B2%5D%5Bkey2%5D=value2 QueryStringBuilder.BuildQueryString(new { Age = 19, Name = "John&Doe", Values = new object[] { 1, 2, new Dictionary<string, string>() { { "key1", "value1" }, { "key2", "value2" }, } }, }); // 0=1&1=2&2%5B0%5D=one&2%5B1%5D=two&2%5B2%5D=three&3%5Bkey1%5D=value1&3%5Bkey2%5D=value2 QueryStringBuilder.BuildQueryString(new object[] { 1, 2, new object[] { "one", "two", "three" }, new Dictionary<string, string>() { { "key1", "value1" }, { "key2", "value2" }, } } );