Improve support to the dictionary returned by ParseQuery

src/Http/Http.Extensions/ref/Microsoft.AspNetCore.Http.Extensions.netcoreapp.cs

@@ -43,6 +43,7 @@ public static partial class HttpRequestMultipartExtensions
     public partial class QueryBuilder : System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<string, string>>, System.Collections.IEnumerable
     {
         public QueryBuilder() { }
+        public QueryBuilder(System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<string, Microsoft.Extensions.Primitives.StringValues>> parameters) { }
         public QueryBuilder(System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<string, string>> parameters) { }
         public void Add(string key, System.Collections.Generic.IEnumerable<string> values) { }
         public void Add(string key, string value) { }

src/Http/Http.Extensions/src/QueryBuilder.cs

@@ -3,8 +3,10 @@
 
 using System.Collections;
 using System.Collections.Generic;
+using System.Linq;
 using System.Text;
 using System.Text.Encodings.Web;
+using Microsoft.Extensions.Primitives;
 
 namespace Microsoft.AspNetCore.Http.Extensions
 {
@@ -23,6 +25,12 @@ public QueryBuilder(IEnumerable<KeyValuePair<string, string>> parameters)
             _params = new List<KeyValuePair<string, string>>(parameters);
         }
 
+        public QueryBuilder(IEnumerable<KeyValuePair<string, StringValues>> parameters)
+            : this(parameters.SelectMany(kvp => kvp.Value, (kvp, v) => KeyValuePair.Create(kvp.Key, v)))
+        {
+
+        }
+
         public void Add(string key, IEnumerable<string> values)
         {
             foreach (var value in values)
@@ -78,4 +86,4 @@ IEnumerator IEnumerable.GetEnumerator()
             return _params.GetEnumerator();
         }
     }
-}
+}

src/Http/Http.Extensions/test/QueryBuilderTests.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using Microsoft.Extensions.Primitives;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Http.Extensions
@@ -70,6 +71,18 @@ public void AddMultipleValuesViaConstructor_AddedInOrder()
             Assert.Equal("?key1=value1&key2=value2&key3=value3", builder.ToString());
         }
 
+        [Fact]
+        public void AddMultipleValuesViaConstructor_WithStringValues()
+        {
+            var builder = new QueryBuilder(new[]
+            {
+                new KeyValuePair<string, StringValues>("key1", new StringValues(new [] { "value1", string.Empty, "value3" })),
+                new KeyValuePair<string, StringValues>("key2", string.Empty),
+                new KeyValuePair<string, StringValues>("key3", StringValues.Empty)
+            });
+            Assert.Equal("?key1=value1&key1=&key1=value3&key2=", builder.ToString());
+        }
+
         [Fact]
         public void AddMultipleValuesViaInitializer_AddedInOrder()
         {
@@ -95,4 +108,4 @@ public void CopyViaConstructor_AddedInOrder()
             Assert.Equal("?key1=value1&key2=value2&key3=value3", builder1.ToString());
         }
     }
-}
+}

src/Http/WebUtilities/ref/Microsoft.AspNetCore.WebUtilities.netcoreapp.cs

@@ -216,6 +216,8 @@ public static partial class MultipartSectionStreamExtensions
     public static partial class QueryHelpers
     {
         public static string AddQueryString(string uri, System.Collections.Generic.IDictionary<string, string> queryString) { throw null; }
+        public static string AddQueryString(string uri, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<string, Microsoft.Extensions.Primitives.StringValues>> queryString) { throw null; }
+        public static string AddQueryString(string uri, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<string, string>> queryString) { throw null; }
         public static string AddQueryString(string uri, string name, string value) { throw null; }
         public static System.Collections.Generic.Dictionary<string, Microsoft.Extensions.Primitives.StringValues> ParseNullableQuery(string queryString) { throw null; }
         public static System.Collections.Generic.Dictionary<string, Microsoft.Extensions.Primitives.StringValues> ParseQuery(string queryString) { throw null; }

src/Http/WebUtilities/src/QueryHelpers.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Text;
 using System.Text.Encodings.Web;
 using Microsoft.Extensions.Primitives;
@@ -46,10 +47,10 @@ public static string AddQueryString(string uri, string name, string value)
         }
 
         /// <summary>
-        /// Append the given query keys and values to the uri.
+        /// Append the given query keys and values to the URI.
         /// </summary>
-        /// <param name="uri">The base uri.</param>
-        /// <param name="queryString">A collection of name value query pairs to append.</param>
+        /// <param name="uri">The base URI.</param>
+        /// <param name="queryString">A dictionary of query keys and values to append.</param>
         /// <returns>The combined result.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="uri"/> is <c>null</c>.</exception>
         /// <exception cref="ArgumentNullException"><paramref name="queryString"/> is <c>null</c>.</exception>
@@ -68,7 +69,38 @@ public static string AddQueryString(string uri, IDictionary<string, string> quer
             return AddQueryString(uri, (IEnumerable<KeyValuePair<string, string>>)queryString);
         }
 
-        private static string AddQueryString(
+        /// <summary>
+        /// Append the given query keys and values to the URI.
+        /// </summary>
+        /// <param name="uri">The base URI.</param>
+        /// <param name="queryString">A collection of query names and values to append.</param>
+        /// <returns>The combined result.</returns>
+        /// <exception cref="ArgumentNullException"><paramref name="uri"/> is <c>null</c>.</exception>
+        /// <exception cref="ArgumentNullException"><paramref name="queryString"/> is <c>null</c>.</exception>
+        public static string AddQueryString(string uri, IEnumerable<KeyValuePair<string, StringValues>> queryString)
+        {
+            if (uri == null)
+            {
+                throw new ArgumentNullException(nameof(uri));
+            }
+
+            if (queryString == null)
+            {
+                throw new ArgumentNullException(nameof(queryString));
+            }
+
+            return AddQueryString(uri, queryString.SelectMany(kvp => kvp.Value, (kvp, v) => KeyValuePair.Create(kvp.Key, v)));
+        }
+
+        /// <summary>
+        /// Append the given query keys and values to the URI.
+        /// </summary>
+        /// <param name="uri">The base URI.</param>
+        /// <param name="queryString">A collection of name value query pairs to append.</param>
+        /// <returns>The combined result.</returns>
+        /// <exception cref="ArgumentNullException"><paramref name="uri"/> is <c>null</c>.</exception>
+        /// <exception cref="ArgumentNullException"><paramref name="queryString"/> is <c>null</c>.</exception>
+        public static string AddQueryString(
             string uri,
             IEnumerable<KeyValuePair<string, string>> queryString)
         {

src/Http/WebUtilities/test/QueryHelpersTests.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using Microsoft.Extensions.Primitives;
 using Xunit;
 
 namespace Microsoft.AspNetCore.WebUtilities
@@ -119,5 +120,37 @@ public void AddQueryStringWithDictionary(string uri, string expectedUri)
             var result = QueryHelpers.AddQueryString(uri, queryStrings);
             Assert.Equal(expectedUri, result);
         }
+
+        [Theory]
+        [InlineData("http://contoso.com/", "http://contoso.com/?param1=value1&param1=&param1=value3&param2=")]
+        [InlineData("http://contoso.com/someaction", "http://contoso.com/someaction?param1=value1&param1=&param1=value3&param2=")]
+        [InlineData("http://contoso.com/someaction?param2=1", "http://contoso.com/someaction?param2=1&param1=value1&param1=&param1=value3&param2=")]
+        [InlineData("http://contoso.com/some#action", "http://contoso.com/some?param1=value1&param1=&param1=value3&param2=#action")]
+        [InlineData("http://contoso.com/some?param2=1#action", "http://contoso.com/some?param2=1&param1=value1&param1=&param1=value3&param2=#action")]
+        [InlineData("http://contoso.com/#action", "http://contoso.com/?param1=value1&param1=&param1=value3&param2=#action")]
+        [InlineData(
+            "http://contoso.com/someaction?q=test#anchor?value",
+            "http://contoso.com/someaction?q=test&param1=value1&param1=&param1=value3&param2=#anchor?value")]
+        [InlineData(
+            "http://contoso.com/someaction#anchor?stuff",
+            "http://contoso.com/someaction?param1=value1&param1=&param1=value3&param2=#anchor?stuff")]
+        [InlineData(
+            "http://contoso.com/someaction?name?something",
+            "http://contoso.com/someaction?name?something&param1=value1&param1=&param1=value3&param2=")]
+        [InlineData(
+            "http://contoso.com/someaction#name#something",
+            "http://contoso.com/someaction?param1=value1&param1=&param1=value3&param2=#name#something")]
+        public void AddQueryStringWithEnumerableOfKeysAndStringValues(string uri, string expectedUri)
+        {
+            var queryStrings = new Dictionary<string, StringValues>()
+                        {
+                            { "param1", new StringValues(new [] { "value1", string.Empty, "value3" }) },
+                            { "param2", string.Empty },
+                            { "param3", StringValues.Empty }
+                        };
+
+            var result = QueryHelpers.AddQueryString(uri, queryStrings);
+            Assert.Equal(expectedUri, result);
+        }
     }
 }