diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Extensions/WechatTenpayClientExecuteXDCExtensions.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Extensions/WechatTenpayClientExecuteXDCExtensions.cs
new file mode 100644
index 00000000..137d5ada
--- /dev/null
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Extensions/WechatTenpayClientExecuteXDCExtensions.cs
@@ -0,0 +1,41 @@
+using System;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Flurl.Http;
+
+namespace SKIT.FlurlHttpClient.Wechat.TenpayV2
+{
+    public static class WechatTenpayClientExecuteXDCExtensions
+    {
+        /// <summary>
+        /// <para>异步调用 [POST] /xdc/apiv2getsignkey/sign/getsignkey 接口。</para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/micropay.php?chapter=23_1&index=1 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/jsapi.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/native.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/app/app.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/H5.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/wxa/wxa_api.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/micropay_sl.php?chapter=23_1&index=1 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/jsapi_sl.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/native_sl.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/app/app_sl.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/H5_sl.php?chapter=23_1&index=2 </para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/api/wxa/wxa_sl_api.php?chapter=23_1&index=2 </para>
+        /// </summary>
+        /// <param name="client"></param>
+        /// <param name="request"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public static async Task<Models.GetSandboxSignKeyResponse> ExecuteGetSandboxSignKeyAsync(this WechatTenpayClient client, Models.GetSandboxSignKeyRequest request, CancellationToken cancellationToken = default)
+        {
+            if (client is null) throw new ArgumentNullException(nameof(client));
+            if (request is null) throw new ArgumentNullException(nameof(request));
+
+            IFlurlRequest flurlReq = client
+                .CreateRequest(request, HttpMethod.Post, "xdc", "apiv2getsignkey", "sign", "getsignkey");
+
+            return await client.SendRequestWithXmlAsync<Models.GetSandboxSignKeyResponse>(flurlReq, data: request, cancellationToken: cancellationToken);
+        }
+    }
+}
diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Models/XDC/GetSandboxSignKeyRequest.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Models/XDC/GetSandboxSignKeyRequest.cs
new file mode 100644
index 00000000..f97f7a08
--- /dev/null
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Models/XDC/GetSandboxSignKeyRequest.cs
@@ -0,0 +1,22 @@
+namespace SKIT.FlurlHttpClient.Wechat.TenpayV2.Models
+{
+    /// <summary>
+    /// <para>表示 [POST] /xdc/apiv2getsignkey/sign/getsignkey 接口的请求。</para>
+    /// </summary>
+    public class GetSandboxSignKeyRequest : WechatTenpaySignableRequest
+    {
+        /// <summary>
+        /// <inheritdoc/>
+        /// </summary>
+        [Newtonsoft.Json.JsonProperty("mch_id")]
+        [System.Text.Json.Serialization.JsonPropertyName("mch_id")]
+        public override string? MerchantId { get; set; }
+
+        /// <summary>
+        /// <inheritdoc/>
+        /// </summary>
+        [Newtonsoft.Json.JsonIgnore]
+        [System.Text.Json.Serialization.JsonIgnore]
+        public override string? AppId { get; set; }
+    }
+}
diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Models/XDC/GetSandboxSignKeyResponse.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Models/XDC/GetSandboxSignKeyResponse.cs
new file mode 100644
index 00000000..07ddc366
--- /dev/null
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/Models/XDC/GetSandboxSignKeyResponse.cs
@@ -0,0 +1,29 @@
+namespace SKIT.FlurlHttpClient.Wechat.TenpayV2.Models
+{
+    /// <summary>
+    /// <para>表示 [POST] /xdc/apiv2getsignkey/sign/getsignkey 接口的响应。</para>
+    /// </summary>
+    public class GetSandboxSignKeyResponse : WechatTenpaySignableResponse
+    {
+        /// <summary>
+        /// <inheritdoc/>
+        /// </summary>
+        [Newtonsoft.Json.JsonProperty("mch_id")]
+        [System.Text.Json.Serialization.JsonPropertyName("mch_id")]
+        public override string? MerchantId { get; set; }
+
+        /// <summary>
+        /// <inheritdoc/>
+        /// </summary>
+        [Newtonsoft.Json.JsonIgnore]
+        [System.Text.Json.Serialization.JsonIgnore]
+        public override string? AppId { get; set; }
+
+        /// <summary>
+        /// 获取或设置沙箱密钥。
+        /// </summary>
+        [Newtonsoft.Json.JsonProperty("sandbox_signkey")]
+        [System.Text.Json.Serialization.JsonPropertyName("sandbox_signkey")]
+        public string SandboxSignKey { get; set; } = default!;
+    }
+}
diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayRequest.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayRequest.cs
index fd58389f..62f2659e 100644
--- a/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayRequest.cs
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayRequest.cs
@@ -1,4 +1,4 @@
-namespace SKIT.FlurlHttpClient.Wechat.TenpayV2
+namespace SKIT.FlurlHttpClient.Wechat.TenpayV2
 {
     /// <summary>
     /// 表示微信支付 API 请求的基类。
@@ -21,6 +21,7 @@
 
         /// <summary>
         /// 获取或设置微信 AppId。如果不指定将使用构造 <see cref="WechatTenpayClient"/> 时的 <see cref="WechatTenpayClientOptions.AppId"/> 参数。
+        /// <para>注意：部分接口不支持指定，请直接忽略此字段。</para>
         /// </summary>
         [Newtonsoft.Json.JsonIgnore]
         [System.Text.Json.Serialization.JsonIgnore]
@@ -40,7 +41,8 @@
         public virtual string? NonceString { get; set; }
 
         /// <summary>
-        /// 获取或设置签名方式。需注意部分接口不支持指定签名方式。
+        /// 获取或设置签名方式。
+        /// <para>注意：部分接口不支持指定签名方式，请直接忽略此字段。</para>
         /// </summary>
         [Newtonsoft.Json.JsonProperty("sign_type")]
         [System.Text.Json.Serialization.JsonPropertyName("sign_type")]
diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayResponse.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayResponse.cs
index f0f03ce2..39c177f1 100644
--- a/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayResponse.cs
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV2/WechatTenpayResponse.cs
@@ -1,4 +1,4 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
 
 namespace SKIT.FlurlHttpClient.Wechat.TenpayV2
 {
@@ -106,6 +106,7 @@ namespace SKIT.FlurlHttpClient.Wechat.TenpayV2
 
         /// <summary>
         /// 获取或设置微信 AppId。
+        /// <para>注意：部分接口不支持获取，请直接忽略此字段。</para>
         /// </summary>
         [Newtonsoft.Json.JsonIgnore]
         [System.Text.Json.Serialization.JsonIgnore]
diff --git a/test/SKIT.FlurlHttpClient.Wechat.TenpayV2.UnitTests/ModelSamples/XDC/GetSandboxSignKeyRequest.json b/test/SKIT.FlurlHttpClient.Wechat.TenpayV2.UnitTests/ModelSamples/XDC/GetSandboxSignKeyRequest.json
new file mode 100644
index 00000000..1f178c9b
--- /dev/null
+++ b/test/SKIT.FlurlHttpClient.Wechat.TenpayV2.UnitTests/ModelSamples/XDC/GetSandboxSignKeyRequest.json
@@ -0,0 +1,5 @@
+{
+    "mch_id": "1305638280",
+    "nonce_str": "5K8264ILTKCH16CQ2502SI8ZNMTM67VS",
+    "sign": "5K8264ILTKCH16CQ2502SI8ZNMTM67VS"
+}
diff --git a/test/SKIT.FlurlHttpClient.Wechat.TenpayV2.UnitTests/ModelSamples/XDC/GetSandboxSignKeyResponse.json b/test/SKIT.FlurlHttpClient.Wechat.TenpayV2.UnitTests/ModelSamples/XDC/GetSandboxSignKeyResponse.json
new file mode 100644
index 00000000..3c0c922b
--- /dev/null
+++ b/test/SKIT.FlurlHttpClient.Wechat.TenpayV2.UnitTests/ModelSamples/XDC/GetSandboxSignKeyResponse.json
@@ -0,0 +1,6 @@
+{
+    "return_code": "SUCCESS",
+    "return_msg": "签名失败",
+    "mch_id": "1305638280",
+    "sandbox_signkey": "013467007045764"
+}