對於.NET的開發者，想要存取 FHIR Server上的資料，透過 FhirClient 物件來操作，是最為方便與簡潔的作法，想要使用這個物件，在 .NET 下主要需要安裝 Firely SDK（前身是 FHIR .NET API），在這裡的例子將會安裝了 Hl7.Fhir.R4 套件。
一旦安裝了安裝了 Hl7.Fhir.R4 套件之後，就可以在程式碼中使用 FhirClient 物件來對 FHIR Server 進行各種操作，例如讀取、查詢、更新、刪除等。可以想像你要去醫院查病歷資料，FhirClient 就像是一個「翻譯員 + 信差」：
- 翻譯員角色：把你的請求（「我要查某個病人的資料」）翻譯成 FHIR 伺服器能懂的語言
- 信差角色：幫你把請求送到伺服器，再把結果帶回來給你
因此，面對 FHIR Server 中超過上百個 Resource，操作起來更加輕鬆雨容易，這裡可以做到這些實際用途，例如：讀取病人資料（Patient）、查詢檢驗結果（Observation）、取得用藥記錄（Medication）、新增或更新醫療資料等。
就技術上來說，FhirClient 是一個程式庫（library），封裝了 HTTP 請求、資料格式轉換、錯誤處理等複雜細節，讓開發者可以用簡單的程式碼就能存取 FHIR 醫療資料，不用自己處理那些繁瑣的通訊協定和資料格式。簡單來說，它就是讓程式開發者能輕鬆存取 FHIR 醫療資料標準系統的工具。
有些時候，開發者可能會想要知道 FhirClient 在背後實際傳送了什麼 HTTP 請求，或是伺服器回傳了什麼樣的 HTTP 回應，這對於除錯、效能優化、了解系統行為等都很有幫助。甚至可以透過這些 HTTP 請求與回應，更深入的取學習與理解 FHIR API 的用法。
public class HttpLoggingHandler : DelegatingHandler
{
protected override async Task<HttpResponseMessage> SendAsync(
HttpRequestMessage request, CancellationToken cancellationToken)
{
var startTime = DateTime.UtcNow;
// 記錄請求
Console.WriteLine("===== HTTP 請求 =====");
Console.WriteLine($"{request.Method} {request.RequestUri}");
Console.WriteLine("標頭:");
foreach (var header in request.Headers)
{
Console.WriteLine($" {header.Key}: {string.Join(", ", header.Value)}");
}
if (request.Content != null)
{
foreach (var header in request.Content.Headers)
{
Console.WriteLine($" {header.Key}: {string.Join(", ", header.Value)}");
}
var requestBody = await request.Content.ReadAsStringAsync(cancellationToken);
if (!string.IsNullOrEmpty(requestBody))
{
Console.WriteLine("請求內容:");
Console.WriteLine(requestBody);
}
}
// 發送請求
var response = await base.SendAsync(request, cancellationToken);
var duration = DateTime.UtcNow - startTime;
// 記錄回應
Console.WriteLine("\n===== HTTP 回應 =====");
Console.WriteLine($"狀態: {(int)response.StatusCode} {response.StatusCode}");
Console.WriteLine("標頭:");
foreach (var header in response.Headers)
{
Console.WriteLine($" {header.Key}: {string.Join(", ", header.Value)}");
}
if (response.Content != null)
{
foreach (var header in response.Content.Headers)
{
Console.WriteLine($" {header.Key}: {string.Join(", ", header.Value)}");
}
var responseBody = await response.Content.ReadAsStringAsync(cancellationToken);
if (!string.IsNullOrEmpty(responseBody))
{
Console.WriteLine("回應內容:");
Console.WriteLine(responseBody);
}
}
Console.WriteLine($"耗時: {duration.TotalMilliseconds:F2} ms");
Console.WriteLine("".PadRight(50, '='));
return response;
}
}- [DelegatingHandler 類別] (https://learn.microsoft.com/zh-tw/dotnet/api/system.net.http.delegatinghandler?view=net-8.0) 是 .NET 提供的一個抽象類別，可以用來建立自訂的 HTTP 處理器（Handler）。這些處理器可以用來攔截、修改、記錄或處理 HTTP 請求和回應。透過繼承 DelegatingHandler，開發者可以實現自己的邏輯，並將其插入到 HTTP 請求管道中。
- 這裡新建立的 [HttpLoggingHandler] 類別將會繼承了這個 [DelegatingHandler] 類別，因此，可以用來攔截 HTTP 請求與回應，並記錄相關的資訊，例如請求方法、URL、標頭、內容，以及回應的狀態碼、標頭、內容等。
- 此類別覆寫了 [SendAsync] 方法，這個方法會在每次發送 HTTP 請求時被呼叫。
- 在這個方法中，我們先記錄請求的詳細資訊，然後呼叫
base.SendAsync方法來發送請求，接著再記錄回應的詳細資訊。最後，將回應物件返回。 - 這裡也會將 HTTP Header 的資訊與內容（Content）都記錄下來，方便後續查看。
- 當 [SendAsync] 方法被呼叫後，會得到一個 [HttpResponseMessage] 物件，代表伺服器的回應。
- 有了這個物件，便可以取得此次 HTTP 回應的原始內容，例如狀態碼、標頭、內容等，並將這些資訊記錄下來。
- 最後，這個類別也會計算出每次呼叫 FHIR API 需要花費的時間成本。
- 這樣一來，每次透過 FhirClient 發送的 HTTP 請求與回應，都會被這個處理器攔截並記錄，方便開發者查看實際的 HTTP Payload。
- 在 [Program.cs] 檔案中，找到
var httpClient = new HttpClient();這一行程式碼，將其修改為以下內容：
var httpHandler = new HttpClientHandler();
var loggingHandler = new HttpLoggingHandler { InnerHandler = httpHandler };
var httpClient = new HttpClient(loggingHandler);- 這段程式碼中，我們先建立了一個 [HttpClientHandler] 物件，這是 .NET 提供的預設 HTTP 處理器，負責處理實際的 HTTP 通訊。
- 接著，我們建立了一個 [HttpLoggingHandler] 物件，並將剛剛建立的 [HttpClientHandler] 設定為它的 [InnerHandler]，這樣當 [HttpLoggingHandler] 收到請求時，就會將請求傳遞給內部的 [HttpClientHandler] 來處理。
- 最後，我們使用這個 [HttpLoggingHandler] 來建立 [HttpClient] 物件，這樣所有透過這個 [HttpClient] 發送的請求，都會先經過我們的日誌處理器，從而記錄下詳細的 HTTP 請求與回應資訊。
- 這樣一來，當我們使用 FhirClient 進行各種操作時，例如讀取病人資料、查詢檢驗結果等，都會觸發我們的 [HttpLoggingHandler]，從而在控制台中看到詳細的 HTTP 請求與回應內容，方便我們進行除錯與分析。
- 執行 [csPatientCRUD] 專案，觀察控制台輸出
Creating Patient ...
JSON: {"resourceType":"Patient","identifier":[{"system":"http://example.org/mrn","value":"MRN-20240814A1"}],"active":true,"name":[{"family":"Lee","given":["Vulcan20250814111"]}],"telecom":[{"system":"phone","value":"0912-345-678","use":"mobile"}],"gender":"female","birthDate":"1990-01-01"}
===== HTTP 請求 =====
POST https://hapi.fhir.org/baseR4/Patient
標頭:
Accept: application/fhir+json
Accept-Charset: utf-8
User-Agent: firely-sdk-client/5.12.1
Content-Type: application/fhir+json; charset=utf-8
請求內容:
{"resourceType":"Patient","identifier":[{"system":"http://example.org/mrn","value":"MRN-20240814A1"}],"active":true,"name":[{"family":"Lee","given":["Vulcan20250814111"]}],"telecom":[{"system":"phone","value":"0912-345-678","use":"mobile"}],"gender":"female","birthDate":"1990-01-01"}
===== HTTP 回應 =====
狀態: 201 Created
標頭:
Server: nginx/1.24.0, (Ubuntu)
Date: Tue, 13 Jan 2026 08:29:11 GMT
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: HAPI FHIR 8.5.3-SNAPSHOT/e3a3c5f741/2025-08-28 REST Server (FHIR Server; FHIR 4.0.1/R4)
ETag: W/"1"
X-Request-ID: I9kYzrNbqdbmsueL
Location: https://hapi.fhir.org/baseR4/Patient/53805146/_history/1
Content-Type: application/fhir+json; charset=utf-8
Content-Location: https://hapi.fhir.org/baseR4/Patient/53805146/_history/1
Last-Modified: Tue, 13 Jan 2026 08:29:11 GMT
回應內容:
{
"resourceType": "Patient",
"id": "53805146",
"meta": {
"versionId": "1",
"lastUpdated": "2026-01-13T08:29:11.623+00:00",
"source": "#I9kYzrNbqdbmsueL"
},
"text": {
"status": "generated",
"div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><div class=\"hapiHeaderText\">Vulcan20250814111 <b>LEE </b></div><table class=\"hapiPropertyTable\"><tbody><tr><td>Identifier</td><td>MRN-20240814A1</td></tr><tr><td>Date of birth</td><td><span>01 January 1990</span></td></tr></tbody></table></div>"
},
"identifier": [ {
"system": "http://example.org/mrn",
"value": "MRN-20240814A1"
} ],
"active": true,
"name": [ {
"family": "Lee",
"given": [ "Vulcan20250814111" ]
} ],
"telecom": [ {
"system": "phone",
"value": "0912-345-678",
"use": "mobile"
} ],
"gender": "female",
"birthDate": "1990-01-01"
}
耗時: 1122.91 ms
==================================================
Created: id=53805146, version=1
Press any key to continue...
Reading Patient by id ...
===== HTTP 請求 =====
GET https://hapi.fhir.org/baseR4/Patient/53805146
標頭:
Accept: application/fhir+json
Accept-Charset: utf-8
User-Agent: firely-sdk-client/5.12.1
===== HTTP 回應 =====
狀態: 200 OK
標頭:
Server: nginx/1.24.0, (Ubuntu)
Date: Tue, 13 Jan 2026 08:29:14 GMT
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: HAPI FHIR 8.5.3-SNAPSHOT/e3a3c5f741/2025-08-28 REST Server (FHIR Server; FHIR 4.0.1/R4)
ETag: W/"1"
X-Request-ID: 6eD6YAfNWkKzdFl5
Content-Type: application/fhir+json; charset=utf-8
Content-Location: https://hapi.fhir.org/baseR4/Patient/53805146/_history/1
Last-Modified: Tue, 13 Jan 2026 08:29:11 GMT
回應內容:
{
"resourceType": "Patient",
"id": "53805146",
"meta": {
"versionId": "1",
"lastUpdated": "2026-01-13T08:29:11.623+00:00",
"source": "#I9kYzrNbqdbmsueL"
},
"text": {
"status": "generated",
"div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><div class=\"hapiHeaderText\">Vulcan20250814111 <b>LEE </b></div><table class=\"hapiPropertyTable\"><tbody><tr><td>Identifier</td><td>MRN-20240814A1</td></tr><tr><td>Date of birth</td><td><span>01 January 1990</span></td></tr></tbody></table></div>"
},
"identifier": [ {
"system": "http://example.org/mrn",
"value": "MRN-20240814A1"
} ],
"active": true,
"name": [ {
"family": "Lee",
"given": [ "Vulcan20250814111" ]
} ],
"telecom": [ {
"system": "phone",
"value": "0912-345-678",
"use": "mobile"
} ],
"gender": "female",
"birthDate": "1990-01-01"
}
耗時: 200.41 ms
==================================================
Read: Vulcan20250814111 Lee | active=True
Press any key to continue...
Updating Patient (add email, set active=false) ...
===== HTTP 請求 =====
PUT https://hapi.fhir.org/baseR4/Patient/53805146
標頭:
Accept: application/fhir+json
Accept-Charset: utf-8
User-Agent: firely-sdk-client/5.12.1
Content-Type: application/fhir+json; charset=utf-8
Last-Modified: Tue, 13 Jan 2026 08:29:11 GMT
請求內容:
{"resourceType":"Patient","id":"53805146","meta":{"versionId":"1","lastUpdated":"2026-01-13T08:29:11.623+00:00","source":"#I9kYzrNbqdbmsueL"},"text":{"status":"generated","div":"<div xmlns=\"http://www.w3.org/1999/xhtml\"><div class=\"hapiHeaderText\">Vulcan20250814111 <b>LEE </b></div><table class=\"hapiPropertyTable\"><tbody><tr><td>Identifier</td><td>MRN-20240814A1</td></tr><tr><td>Date of birth</td><td><span>01 January 1990</span></td></tr></tbody></table></div>"},"identifier":[{"system":"http://example.org/mrn","value":"MRN-20240814A1"}],"active":false,"name":[{"family":"Lee","given":["Vulcan20250814111"]}],"telecom":[{"system":"phone","value":"0912-345-678","use":"mobile"},{"system":"email","value":"Vulcan20250814111.Lee@example.org"}],"gender":"female","birthDate":"1990-01-01"}
===== HTTP 回應 =====
狀態: 200 OK
標頭:
Server: nginx/1.24.0, (Ubuntu)
Date: Tue, 13 Jan 2026 08:29:17 GMT
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: HAPI FHIR 8.5.3-SNAPSHOT/e3a3c5f741/2025-08-28 REST Server (FHIR Server; FHIR 4.0.1/R4)
ETag: W/"2"
X-Request-ID: etoip1zPped1yLq4
Content-Type: application/fhir+json; charset=utf-8
Content-Location: https://hapi.fhir.org/baseR4/Patient/53805146/_history/2
Last-Modified: Tue, 13 Jan 2026 08:29:17 GMT
回應內容:
{
"resourceType": "Patient",
"id": "53805146",
"meta": {
"versionId": "2",
"lastUpdated": "2026-01-13T08:29:17.196+00:00",
"source": "#etoip1zPped1yLq4"
},
"text": {
"status": "generated",
"div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><div class=\"hapiHeaderText\">Vulcan20250814111 <b>LEE </b></div><table class=\"hapiPropertyTable\"><tbody><tr><td>Identifier</td><td>MRN-20240814A1</td></tr><tr><td>Date of birth</td><td><span>01 January 1990</span></td></tr></tbody></table></div>"
},
"identifier": [ {
"system": "http://example.org/mrn",
"value": "MRN-20240814A1"
} ],
"active": false,
"name": [ {
"family": "Lee",
"given": [ "Vulcan20250814111" ]
} ],
"telecom": [ {
"system": "phone",
"value": "0912-345-678",
"use": "mobile"
}, {
"system": "email",
"value": "Vulcan20250814111.Lee@example.org"
} ],
"gender": "female",
"birthDate": "1990-01-01"
}
耗時: 232.04 ms
==================================================
Updated: version=2, telecom=Phone:0912-345-678, Email:Vulcan20250814111.Lee@example.org
Press any key to continue...
Searching Patient by identifier 'MRN-20240814A1' ...
===== HTTP 請求 =====
GET https://hapi.fhir.org/baseR4/Patient?_count=5&identifier=MRN-20240814A1
標頭:
Accept: application/fhir+json
Accept-Charset: utf-8
User-Agent: firely-sdk-client/5.12.1
===== HTTP 回應 =====
狀態: 200 OK
標頭:
Server: nginx/1.24.0, (Ubuntu)
Date: Tue, 13 Jan 2026 08:29:18 GMT
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: HAPI FHIR 8.5.3-SNAPSHOT/e3a3c5f741/2025-08-28 REST Server (FHIR Server; FHIR 4.0.1/R4)
X-Request-ID: UbbmBpPRELgqIKJ1
Content-Type: application/fhir+json; charset=utf-8
Last-Modified: Tue, 13 Jan 2026 08:29:18 GMT
回應內容:
{
"resourceType": "Bundle",
"id": "3b672bdf-058e-4580-bab8-dbf3e6335188",
"meta": {
"lastUpdated": "2026-01-13T08:29:18.646+00:00"
},
"type": "searchset",
"total": 1,
"link": [ {
"relation": "self",
"url": "https://hapi.fhir.org/baseR4/Patient?_count=5&identifier=MRN-20240814A1"
} ],
"entry": [ {
"fullUrl": "https://hapi.fhir.org/baseR4/Patient/53805146",
"resource": {
"resourceType": "Patient",
"id": "53805146",
"meta": {
"versionId": "2",
"lastUpdated": "2026-01-13T08:29:17.196+00:00",
"source": "#etoip1zPped1yLq4"
},
"text": {
"status": "generated",
"div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><div class=\"hapiHeaderText\">Vulcan20250814111 <b>LEE </b></div><table class=\"hapiPropertyTable\"><tbody><tr><td>Identifier</td><td>MRN-20240814A1</td></tr><tr><td>Date of birth</td><td><span>01 January 1990</span></td></tr></tbody></table></div>"
},
"identifier": [ {
"system": "http://example.org/mrn",
"value": "MRN-20240814A1"
} ],
"active": false,
"name": [ {
"family": "Lee",
"given": [ "Vulcan20250814111" ]
} ],
"telecom": [ {
"system": "phone",
"value": "0912-345-678",
"use": "mobile"
}, {
"system": "email",
"value": "Vulcan20250814111.Lee@example.org"
} ],
"gender": "female",
"birthDate": "1990-01-01"
},
"search": {
"mode": "match"
}
} ]
}
耗時: 207.54 ms
==================================================
Search total (if provided): 1
- 53805146 | Vulcan20250814111 Lee | active=False
Press any key to continue...
Deleting Patient ...
===== HTTP 請求 =====
DELETE https://hapi.fhir.org/baseR4/Patient/53805146
標頭:
Accept: application/fhir+json
Accept-Charset: utf-8
User-Agent: firely-sdk-client/5.12.1
===== HTTP 回應 =====
狀態: 200 OK
標頭:
Server: nginx/1.24.0, (Ubuntu)
Date: Tue, 13 Jan 2026 08:29:21 GMT
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: HAPI FHIR 8.5.3-SNAPSHOT/e3a3c5f741/2025-08-28 REST Server (FHIR Server; FHIR 4.0.1/R4)
X-Request-ID: 483EQAcOrq348Tca
Content-Type: application/fhir+json; charset=utf-8
Content-Location: https://hapi.fhir.org/baseR4/Patient/53805146/_history/3
回應內容:
{
"resourceType": "OperationOutcome",
"text": {
"status": "generated",
"div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><h1>Operation Outcome</h1><table border=\"0\"><tr><td style=\"font-weight: bold;\">INFORMATION</td><td>[]</td><td>Successfully deleted 1 resource(s). Took 18ms.</td></tr></table></div>"
},
"issue": [ {
"severity": "information",
"code": "informational",
"details": {
"coding": [ {
"system": "https://hapifhir.io/fhir/CodeSystem/hapi-fhir-storage-response-code",
"code": "SUCCESSFUL_DELETE",
"display": "Delete succeeded."
} ]
},
"diagnostics": "Successfully deleted 1 resource(s). Took 18ms."
} ]
}
耗時: 226.93 ms
==================================================
Deleted.
===== HTTP 請求 =====
GET https://hapi.fhir.org/baseR4/Patient/53805146
標頭:
Accept: application/fhir+json
Accept-Charset: utf-8
User-Agent: firely-sdk-client/5.12.1
===== HTTP 回應 =====
狀態: 410 Gone
標頭:
Server: nginx/1.24.0, (Ubuntu)
Date: Tue, 13 Jan 2026 08:29:22 GMT
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: HAPI FHIR 8.5.3-SNAPSHOT/e3a3c5f741/2025-08-28 REST Server (FHIR Server; FHIR 4.0.1/R4)
X-Request-ID: bxMyna52dXXlZoKB
Location: https://hapi.fhir.org/baseR4/Patient/53805146/_history/3
Content-Type: application/fhir+json; charset=utf-8
回應內容:
{
"resourceType": "OperationOutcome",
"text": {
"status": "generated",
"div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><h1>Operation Outcome</h1><table border=\"0\"><tr><td style=\"font-weight: bold;\">ERROR</td><td>[]</td><td>Resource was deleted at 2026-01-13T08:29:21.412+00:00</td></tr></table></div>"
},
"issue": [ {
"severity": "error",
"code": "processing",
"diagnostics": "Resource was deleted at 2026-01-13T08:29:21.412+00:00"
} ]
}
耗時: 977.67 ms
==================================================
Confirmed 410 Gone after delete.
Press any key to continue...