Add support for HTMX 2.x

README.md

@@ -5,6 +5,7 @@
 Provides HTMX integration for ASP.NET Core applications.
 
 <!-- TOC -->
+* [HtmxToolkit](#htmxtoolkit)
   * [Getting Started](#getting-started)
   * [HttpRequest](#httprequest)
     * [HtmxRequestAttribute](#htmxrequestattribute)
@@ -14,6 +15,7 @@ Provides HTMX integration for ASP.NET Core applications.
     * [HtmxUrlTagHelper](#htmxurltaghelper)
     * [HtmxHeaderTagHelper](#htmxheadertaghelper)
     * [HtmxConfigTagHelper](#htmxconfigtaghelper)
+      * [Response Handling Configuration](#response-handling-configuration)
   * [Antiforgery Token](#antiforgery-token)
   * [Supported Versions](#supported-versions)
   * [Contributions](#contributions)
@@ -618,6 +620,61 @@ If desired or for the purpose of semantics, you can use `htmx-config` as the sta
              include-antiforgery-token="true" />
 ```
 
+#### Response Handling Configuration
+
+HTMX 2.x introduces the [`responseHandling`](https://htmx.org/docs/#response-handling) configuration option,
+allowing you to define how htmx should handle responses based on HTTP status codes.
+The library provides a child tag helper `<response-handling>` that can be placed inside `<htmx-config>`
+to declaratively configure response handling rules.
+
+```html
+<htmx-config>
+    <!-- 204 No Content — do not swap, but not an error -->
+    <response-handling code="204" swap="false" />
+
+    <!-- 2xx & 3xx — swap into DOM -->
+    <response-handling code="[23].." swap="true" />
+
+    <!-- 422 Unprocessable Entity — swap (e.g. validation errors) -->
+    <response-handling code="422" swap="true" />
+
+    <!-- 4xx & 5xx — do not swap, treat as error -->
+    <response-handling code="[45].." swap="false" error="true" />
+
+    <!-- Catch-all for any other response code -->
+    <response-handling code="..." swap="true" />
+</htmx-config>
+```
+
+The following code will be generated:
+
+```html
+<meta name="htmx-config"
+      content='{"responseHandling":[{"code":"204","swap":false},{"code":"[23]..","swap":true},{"code":"422","swap":true},{"code":"[45]..","swap":false,"error":true},{"code":"...","swap":true}]}' />
+```
+
+The `<response-handling>` element supports the following attributes:
+
+| Attribute       | Type     | Description                                                      |
+|-----------------|----------|------------------------------------------------------------------|
+| `code`          | `string` | Regular expression tested against response status codes          |
+| `swap`          | `bool?`  | Whether the response should be swapped into the DOM              |
+| `error`         | `bool?`  | Whether htmx should treat this response as an error              |
+| `ignore-title`  | `bool?`  | Whether to ignore title tags in the response                     |
+| `select`        | `string` | CSS selector to select content from the response                 |
+| `target`        | `string` | CSS selector specifying an alternative target for the response   |
+| `swap-override` | `string` | Alternative swap mechanism for the response                      |
+
+Alternatively, you can set the entire response handling configuration directly as a Razor expression:
+
+```html
+<htmx-config response-handling="@new [] {
+    new ResponseHandlingEntry { Code = "204", Swap = false },
+    new ResponseHandlingEntry { Code = "[23]..", Swap = true },
+    new ResponseHandlingEntry { Code = "[45]..", Swap = false, Error = true }
+}" />
+```
+
 ## Antiforgery Token
 
 If you have enabled the generation of the **Antiforgery** token in the configuration

src/Ramstack.HtmxToolkit/HtmxScrollBehavior.cs

@@ -13,5 +13,11 @@ public enum HtmxScrollBehavior
     /// <summary>
     /// Specifies smooth scrolling to the top of the page.
     /// </summary>
-    Smooth
+    Smooth,
+
+    /// <summary>
+    /// Specifies instant scrolling with no animation.
+    /// Supported only in HTMX 2.x.
+    /// </summary>
+    Instant
 }

src/Ramstack.HtmxToolkit/Internal/EnumHelper.cs

@@ -20,10 +20,17 @@ public static string GetWsBinaryTypeValue(this HtmxBinaryType value) =>
     /// </summary>
     /// <param name="value">The <see cref="HtmxScrollBehavior"/> value.</param>
     /// <returns>
-    /// The string representation: either "auto" or "smooth".
+    /// The string representation: "auto", "smooth" or "instant".
     /// </returns>
-    public static string GetScrollBehaviorValue(this HtmxScrollBehavior value) =>
-        value == HtmxScrollBehavior.Auto ? "auto" : "smooth";
+    public static string GetScrollBehaviorValue(this HtmxScrollBehavior value)
+    {
+        return value switch
+        {
+            HtmxScrollBehavior.Auto => "auto",
+            HtmxScrollBehavior.Smooth => "smooth",
+            _ => "instant"
+        };
+    }
 
     /// <summary>
     /// Converts a <see cref="HtmxSwap"/> value to its corresponding string representation,
@@ -47,17 +54,17 @@ public static string GetScrollBehaviorValue(this HtmxScrollBehavior value) =>
     /// </returns>
     public static string GetSwapValue(this HtmxSwap value)
     {
-        switch (value)
+        return value switch
         {
-            case HtmxSwap.InnerHtml: return "innerHTML";
-            case HtmxSwap.OuterHtml: return "outerHTML";
-            case HtmxSwap.BeforeBegin: return "beforebegin";
-            case HtmxSwap.AfterBegin: return "afterbegin";
-            case HtmxSwap.BeforeEnd: return "beforeend";
-            case HtmxSwap.AfterEnd: return "afterend";
-            case HtmxSwap.Delete: return "delete";
-            default: return "none";
-        }
+            HtmxSwap.InnerHtml => "innerHTML",
+            HtmxSwap.OuterHtml => "outerHTML",
+            HtmxSwap.BeforeBegin => "beforebegin",
+            HtmxSwap.AfterBegin => "afterbegin",
+            HtmxSwap.BeforeEnd => "beforeend",
+            HtmxSwap.AfterEnd => "afterend",
+            HtmxSwap.Delete => "delete",
+            _ => "none"
+        };
     }
 
     /// <summary>

src/Ramstack.HtmxToolkit/TagHelpers/HtmxConfigJsonSerializerContext.cs

@@ -9,6 +9,7 @@ namespace Ramstack.HtmxToolkit.TagHelpers;
     DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull,
     GenerationMode = JsonSourceGenerationMode.Serialization)]
 [JsonSerializable(typeof(HtmxConfigTagHelper.HtmxConfiguration))]
-[JsonSerializable(typeof(HtmxConfigTagHelper.AntiForgeryTokenData))]
+[JsonSerializable(typeof(HtmxConfigTagHelper.AntiForgeryTokenData?))]
+[JsonSerializable(typeof(IList<ResponseHandlingEntry>))]
 internal partial class HtmxConfigJsonSerializerContext : JsonSerializerContext;
 #endif