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azure-ai-document-intelligence-dotnet

Microsoft ｜ 雲端與基礎設施 ｜ 原文 ｜ MIT

用 .NET SDK 從文件擷取文字、表格，並訓練自訂模型

中文翻譯

---
name: azure-ai-document-intelligence-dotnet
description: |
  Azure AI Document Intelligence SDK（.NET 版）。用預建和自訂模型從文件擷取文字、表格和結構化資料。用於發票處理、收據擷取、身分文件分析和自訂文件模型。Triggers: "Document Intelligence", "DocumentIntelligenceClient", "form recognizer", "invoice extraction", "receipt OCR", "document analysis .NET"。
license: MIT
metadata:
  author: Microsoft
  version: "1.0.0"
  package: Azure.AI.DocumentIntelligence
---

# Azure.AI.DocumentIntelligence（.NET）

用預建和自訂模型從文件擷取文字、表格和結構化資料。

## 安裝

```bash
dotnet add package Azure.AI.DocumentIntelligence
dotnet add package Azure.Identity
```

**目前版本**：v1.0.0（GA）

## 環境變數

```bash
DOCUMENT_INTELLIGENCE_ENDPOINT=https://<resource-name>.cognitiveservices.azure.com/  # 必填：Document Intelligence endpoint
DOCUMENT_INTELLIGENCE_API_KEY=<your-api-key>  # 只有用 AzureKeyCredential 認證時才需要
BLOB_CONTAINER_SAS_URL=https://<storage>.blob.core.windows.net/<container>?<sas-token>  # 選填：訓練資料用的 blob container SAS URL
AZURE_TOKEN_CREDENTIALS=prod  # 只有在正式環境用 DefaultAzureCredential 時才需要
```

## 認證

### Microsoft Entra Token Credential

```csharp
using Azure.Identity;
using Azure.AI.DocumentIntelligence;

string endpoint = Environment.GetEnvironmentVariable("DOCUMENT_INTELLIGENCE_ENDPOINT");
// 本機開發：用 DefaultAzureCredential。正式環境：設定 AZURE_TOKEN_CREDENTIALS=prod 或 AZURE_TOKEN_CREDENTIALS=<specific_credential>
var credential = new DefaultAzureCredential(
    DefaultAzureCredential.DefaultEnvironmentVariableName
);
// 或在正式環境直接使用指定的 credential：
// See https://learn.microsoft.com/dotnet/api/overview/azure/identity-readme?view=azure-dotnet#credential-classes
// var credential = new ManagedIdentityCredential();
var client = new DocumentIntelligenceClient(new Uri(endpoint), credential);
```

> **注意**：Entra ID 需要**自訂子網域**（例如 `https://<resource-name>.cognitiveservices.azure.com/`），不能用區域 endpoint。

### API Key

```csharp
string endpoint = Environment.GetEnvironmentVariable("DOCUMENT_INTELLIGENCE_ENDPOINT");
string apiKey = Environment.GetEnvironmentVariable("DOCUMENT_INTELLIGENCE_API_KEY");
var client = new DocumentIntelligenceClient(new Uri(endpoint), new AzureKeyCredential(apiKey));
```

## Client 類型

| Client | 用途 |
|--------|---------|
| `DocumentIntelligenceClient` | 分析文件、分類文件 |
| `DocumentIntelligenceAdministrationClient` | 建立／管理自訂模型和分類器 |

## 預建模型

| Model ID | 說明 |
|----------|-------------|
| `prebuilt-read` | 擷取文字、語言、手寫內容 |
| `prebuilt-layout` | 擷取文字、表格、勾選標記、結構 |
| `prebuilt-invoice` | 擷取發票欄位（廠商、項目、總額） |
| `prebuilt-receipt` | 擷取收據欄位（商家、項目、總額） |
| `prebuilt-idDocument` | 擷取身分文件欄位（姓名、生日、地址） |
| `prebuilt-businessCard` | 擷取名片欄位 |
| `prebuilt-tax.us.w2` | 擷取 W-2 稅務表單欄位 |
| `prebuilt-healthInsuranceCard.us` | 擷取健康保險卡欄位 |

## 核心流程

### 1. 分析發票

```csharp
using Azure.AI.DocumentIntelligence;

Uri invoiceUri = new Uri("https://example.com/invoice.pdf");

Operation<AnalyzeResult> operation = await client.AnalyzeDocumentAsync(
    WaitUntil.Completed, 
    "prebuilt-invoice", 
    invoiceUri);

AnalyzeResult result = operation.Value;

foreach (AnalyzedDocument document in result.Documents)
{
    if (document.Fields.TryGetValue("VendorName", out DocumentField vendorNameField)
        && vendorNameField.FieldType == DocumentFieldType.String)
    {
        string vendorName = vendorNameField.ValueString;
        Console.WriteLine($"Vendor Name: '{vendorName}', confidence: {vendorNameField.Confidence}");
    }

    if (document.Fields.TryGetValue("InvoiceTotal", out DocumentField invoiceTotalField)
        && invoiceTotalField.FieldType == DocumentFieldType.Currency)
    {
        CurrencyValue invoiceTotal = invoiceTotalField.ValueCurrency;
        Console.WriteLine($"Invoice Total: '{invoiceTotal.CurrencySymbol}{invoiceTotal.Amount}'");
    }
    
    // 擷取明細項目
    if (document.Fields.TryGetValue("Items", out DocumentField itemsField)
        && itemsField.FieldType == DocumentFieldType.List)
    {
        foreach (DocumentField item in itemsField.ValueList)
        {
            var itemFields = item.ValueDictionary;
            if (itemFields.TryGetValue("Description", out DocumentField descField))
                Console.WriteLine($"  Item: {descField.ValueString}");
        }
    }
}
```

### 2. 擷取版面配置（文字、表格、結構）

```csharp
Uri fileUri = new Uri("https://example.com/document.pdf");

Operation<AnalyzeResult> operation = await client.AnalyzeDocumentAsync(
    WaitUntil.Completed, 
    "prebuilt-layout", 
    fileUri);

AnalyzeResult result = operation.Value;

// 依頁面擷取文字
foreach (DocumentPage page in result.Pages)
{
    Console.WriteLine($"Page {page.PageNumber}: {page.Lines.Count} lines, {page.Words.Count} words");
    
    foreach (DocumentLine line in page.Lines)
    {
        Console.WriteLine($"  Line: '{line.Content}'");
    }
}

// 擷取表格
foreach (DocumentTable table in result.Tables)
{
    Console.WriteLine($"Table: {table.RowCount} rows x {table.ColumnCount} columns");
    foreach (DocumentTableCell cell in table.Cells)
    {
        Console.WriteLine($"  Cell ({cell.RowIndex}, {cell.ColumnIndex}): {cell.Content}");
    }
}
```

### 3. 分析收據

```csharp
Operation<AnalyzeResult> operation = await client.AnalyzeDocumentAsync(
    WaitUntil.Completed, 
    "prebuilt-receipt", 
    receiptUri);

AnalyzeResult result = operation.Value;

foreach (AnalyzedDocument document in result.Documents)
{
    if (document.Fields.TryGetValue("MerchantName", out DocumentField merchantField))
        Console.WriteLine($"Merchant: {merchantField.ValueString}");
        
    if (document.Fields.TryGetValue("Total", out DocumentField totalField))
        Console.WriteLine($"Total: {totalField.ValueCurrency.Amount}");
        
    if (document.Fields.TryGetValue("TransactionDate", out DocumentField dateField))
        Console.WriteLine($"Date: {dateField.ValueDate}");
}
```

### 4. 建立自訂模型

```csharp
var adminClient = new DocumentIntelligenceAdministrationClient(
    new Uri(endpoint), 
    new AzureKeyCredential(apiKey));

string modelId = "my-custom-model";
Uri blobContainerUri = new Uri("<blob-container-sas-url>");

var blobSource = new BlobContentSource(blobContainerUri);
var options = new BuildDocumentModelOptions(modelId, DocumentBuildMode.Template, blobSource);

Operation<DocumentModelDetails> operation = await adminClient.BuildDocumentModelAsync(
    WaitUntil.Completed, 
    options);

DocumentModelDetails model = operation.Value;

Console.WriteLine($"Model ID: {model.ModelId}");
Console.WriteLine($"Created: {model.CreatedOn}");

foreach (var docType in model.DocumentTypes)
{
    Console.WriteLine($"Document type: {docType.Key}");
    foreach (var field in docType.Value.FieldSchema)
    {
        Console.WriteLine($"  Field: {field.Key}, Confidence: {docType.Value.FieldConfidence[field.Key]}");
    }
}
```

### 5. 建立文件分類器

```csharp
string classifierId = "my-classifier";
Uri blobContainerUri = new Uri("<blob-container-sas-url>");

var sourceA = new BlobContentSource(blobContainerUri) { Prefix = "TypeA/train" };
var sourceB = new BlobContentSource(blobContainerUri) { Prefix = "TypeB/train" };

var docTypes = new Dictionary<string, ClassifierDocumentTypeDetails>()
{
    { "TypeA", new ClassifierDocumentTypeDetails(sourceA) },
    { "TypeB", new ClassifierDocumentTypeDetails(sourceB) }
};

var options = new BuildClassifierOptions(classifierId, docTypes);

Operation<DocumentClassifierDetails> operation = await adminClient.BuildClassifierAsync(
    WaitUntil.Completed, 
    options);

DocumentClassifierDetails classifier = operation.Value;
Console.WriteLine($"Classifier ID: {classifier.ClassifierId}");
```

### 6. 分類文件

```csharp
string classifierId = "my-classifier";
Uri documentUri = new Uri("https://example.com/document.pdf");

var options = new ClassifyDocumentOptions(classifierId, documentUri);

Operation<AnalyzeResult> operation = await client.ClassifyDocumentAsync(
    WaitUntil.Completed, 
    options);

AnalyzeResult result = operation.Value;

foreach (AnalyzedDocument document in result.Documents)
{
    Console.WriteLine($"Document type: {document.DocumentType}, confidence: {document.Confidence}");
}
```

### 7. 管理模型

```csharp
// 取得資源詳細資訊
DocumentIntelligenceResourceDetails resourceDetails = await adminClient.GetResourceDetailsAsync();
Console.WriteLine($"Custom models: {resourceDetails.CustomDocumentModels.Count}/{resourceDetails.CustomDocumentModels.Limit}");

// 取得指定的模型
DocumentModelDetails model = await adminClient.GetModelAsync("my-model-id");
Console.WriteLine($"Model: {model.ModelId}, Created: {model.CreatedOn}");

// 列出模型
await foreach (DocumentModelDetails modelItem in adminClient.GetModelsAsync())
{
    Console.WriteLine($"Model: {modelItem.ModelId}");
}

// 刪除模型
await adminClient.DeleteModelAsync("my-model-id");
```

## 主要型別參考

| 型別 | 說明 |
|------|-------------|
| `DocumentIntelligenceClient` | 分析用的主要 client |
| `DocumentIntelligenceAdministrationClient` | 模型管理 |
| `AnalyzeResult` | 文件分析的結果 |
| `AnalyzedDocument` | 結果中的單一文件 |
| `DocumentField` | 擷取出的欄位，含值和信心分數 |
| `DocumentFieldType` | String、Date、Number、Currency 等 |
| `DocumentPage` | 頁面資訊（行、字、勾選標記） |
| `DocumentTable` | 擷取出的表格及其儲存格 |
| `DocumentModelDetails` | 自訂模型的 metadata |
| `BlobContentSource` | 訓練資料來源 |

## 建置模式

| 模式 | 使用情境 |
|------|----------|
| `DocumentBuildMode.Template` | 版面固定的文件（表單） |
| `DocumentBuildMode.Neural` | 版面不固定的文件 |

## 最佳實務

1. 正式環境**用 DefaultAzureCredential**
2. **重複使用 client 實例**：client 是 thread-safe 的
3. **處理長時間執行的操作**：要簡單的話用 `WaitUntil.Completed`
4. **檢查欄位信心分數**：一定要驗證 `Confidence` 屬性
5. **選對模型**：常見文件用預建的，特殊文件用自訂的
6. **用自訂子網域**：Entra ID 認證必須使用

## 錯誤處理

```csharp
using Azure;

try
{
    var operation = await client.AnalyzeDocumentAsync(
        WaitUntil.Completed, 
        "prebuilt-invoice", 
        documentUri);
}
catch (RequestFailedException ex)
{
    Console.WriteLine($"Error: {ex.Status} - {ex.Message}");
}
```

## 相關 SDK

| SDK | 用途 | 安裝 |
|-----|---------|---------|
| `Azure.AI.DocumentIntelligence` | 文件分析（本 SDK） | `dotnet add package Azure.AI.DocumentIntelligence` |
| `Azure.AI.FormRecognizer` | 舊版 SDK（已棄用） | 改用 DocumentIntelligence |

## 參考連結

| 資源 | URL |
|----------|-----|
| NuGet 套件 | https://www.nuget.org/packages/Azure.AI.DocumentIntelligence |
| API 參考 | https://learn.microsoft.com/dotnet/api/azure.ai.documentintelligence |
| GitHub 範例 | https://github.com/Azure/azure-sdk-for-net/tree/main/sdk/documentintelligence/Azure.AI.DocumentIntelligence/samples |
| Document Intelligence Studio | https://documentintelligence.ai.azure.com/ |
| 預建模型 | https://aka.ms/azsdk/formrecognizer/models |

英文原文

---
name: azure-ai-document-intelligence-dotnet
description: |
  Azure AI Document Intelligence SDK for .NET. Extract text, tables, and structured data from documents using prebuilt and custom models. Use for invoice processing, receipt extraction, ID document analysis, and custom document models. Triggers: "Document Intelligence", "DocumentIntelligenceClient", "form recognizer", "invoice extraction", "receipt OCR", "document analysis .NET".
license: MIT
metadata:
  author: Microsoft
  version: "1.0.0"
  package: Azure.AI.DocumentIntelligence
---

# Azure.AI.DocumentIntelligence (.NET)

Extract text, tables, and structured data from documents using prebuilt and custom models.

## Installation

```bash
dotnet add package Azure.AI.DocumentIntelligence
dotnet add package Azure.Identity
```

**Current Version**: v1.0.0 (GA)

## Environment Variables

```bash
DOCUMENT_INTELLIGENCE_ENDPOINT=https://<resource-name>.cognitiveservices.azure.com/  # Required: Document Intelligence endpoint
DOCUMENT_INTELLIGENCE_API_KEY=<your-api-key>  # Only required for AzureKeyCredential auth
BLOB_CONTAINER_SAS_URL=https://<storage>.blob.core.windows.net/<container>?<sas-token>  # Optional: blob container SAS URL for training data
AZURE_TOKEN_CREDENTIALS=prod  # Required only if DefaultAzureCredential is used in production
```

## Authentication

### Microsoft Entra Token Credential

```csharp
using Azure.Identity;
using Azure.AI.DocumentIntelligence;

string endpoint = Environment.GetEnvironmentVariable("DOCUMENT_INTELLIGENCE_ENDPOINT");
// Local dev: DefaultAzureCredential. Production: set AZURE_TOKEN_CREDENTIALS=prod or AZURE_TOKEN_CREDENTIALS=<specific_credential>
var credential = new DefaultAzureCredential(
    DefaultAzureCredential.DefaultEnvironmentVariableName
);
// Or use a specific credential directly in production:
// See https://learn.microsoft.com/dotnet/api/overview/azure/identity-readme?view=azure-dotnet#credential-classes
// var credential = new ManagedIdentityCredential();
var client = new DocumentIntelligenceClient(new Uri(endpoint), credential);
```

> **Note**: Entra ID requires a **custom subdomain** (e.g., `https://<resource-name>.cognitiveservices.azure.com/`), not a regional endpoint.

### API Key

```csharp
string endpoint = Environment.GetEnvironmentVariable("DOCUMENT_INTELLIGENCE_ENDPOINT");
string apiKey = Environment.GetEnvironmentVariable("DOCUMENT_INTELLIGENCE_API_KEY");
var client = new DocumentIntelligenceClient(new Uri(endpoint), new AzureKeyCredential(apiKey));
```

## Client Types

| Client | Purpose |
|--------|---------|
| `DocumentIntelligenceClient` | Analyze documents, classify documents |
| `DocumentIntelligenceAdministrationClient` | Build/manage custom models and classifiers |

## Prebuilt Models

| Model ID | Description |
|----------|-------------|
| `prebuilt-read` | Extract text, languages, handwriting |
| `prebuilt-layout` | Extract text, tables, selection marks, structure |
| `prebuilt-invoice` | Extract invoice fields (vendor, items, totals) |
| `prebuilt-receipt` | Extract receipt fields (merchant, items, total) |
| `prebuilt-idDocument` | Extract ID document fields (name, DOB, address) |
| `prebuilt-businessCard` | Extract business card fields |
| `prebuilt-tax.us.w2` | Extract W-2 tax form fields |
| `prebuilt-healthInsuranceCard.us` | Extract health insurance card fields |

## Core Workflows

### 1. Analyze Invoice

```csharp
using Azure.AI.DocumentIntelligence;

Uri invoiceUri = new Uri("https://example.com/invoice.pdf");

Operation<AnalyzeResult> operation = await client.AnalyzeDocumentAsync(
    WaitUntil.Completed, 
    "prebuilt-invoice", 
    invoiceUri);

AnalyzeResult result = operation.Value;

foreach (AnalyzedDocument document in result.Documents)
{
    if (document.Fields.TryGetValue("VendorName", out DocumentField vendorNameField)
        && vendorNameField.FieldType == DocumentFieldType.String)
    {
        string vendorName = vendorNameField.ValueString;
        Console.WriteLine($"Vendor Name: '{vendorName}', confidence: {vendorNameField.Confidence}");
    }

    if (document.Fields.TryGetValue("InvoiceTotal", out DocumentField invoiceTotalField)
        && invoiceTotalField.FieldType == DocumentFieldType.Currency)
    {
        CurrencyValue invoiceTotal = invoiceTotalField.ValueCurrency;
        Console.WriteLine($"Invoice Total: '{invoiceTotal.CurrencySymbol}{invoiceTotal.Amount}'");
    }
    
    // Extract line items
    if (document.Fields.TryGetValue("Items", out DocumentField itemsField)
        && itemsField.FieldType == DocumentFieldType.List)
    {
        foreach (DocumentField item in itemsField.ValueList)
        {
            var itemFields = item.ValueDictionary;
            if (itemFields.TryGetValue("Description", out DocumentField descField))
                Console.WriteLine($"  Item: {descField.ValueString}");
        }
    }
}
```

### 2. Extract Layout (Text, Tables, Structure)

```csharp
Uri fileUri = new Uri("https://example.com/document.pdf");

Operation<AnalyzeResult> operation = await client.AnalyzeDocumentAsync(
    WaitUntil.Completed, 
    "prebuilt-layout", 
    fileUri);

AnalyzeResult result = operation.Value;

// Extract text by page
foreach (DocumentPage page in result.Pages)
{
    Console.WriteLine($"Page {page.PageNumber}: {page.Lines.Count} lines, {page.Words.Count} words");
    
    foreach (DocumentLine line in page.Lines)
    {
        Console.WriteLine($"  Line: '{line.Content}'");
    }
}

// Extract tables
foreach (DocumentTable table in result.Tables)
{
    Console.WriteLine($"Table: {table.RowCount} rows x {table.ColumnCount} columns");
    foreach (DocumentTableCell cell in table.Cells)
    {
        Console.WriteLine($"  Cell ({cell.RowIndex}, {cell.ColumnIndex}): {cell.Content}");
    }
}
```

### 3. Analyze Receipt

```csharp
Operation<AnalyzeResult> operation = await client.AnalyzeDocumentAsync(
    WaitUntil.Completed, 
    "prebuilt-receipt", 
    receiptUri);

AnalyzeResult result = operation.Value;

foreach (AnalyzedDocument document in result.Documents)
{
    if (document.Fields.TryGetValue("MerchantName", out DocumentField merchantField))
        Console.WriteLine($"Merchant: {merchantField.ValueString}");
        
    if (document.Fields.TryGetValue("Total", out DocumentField totalField))
        Console.WriteLine($"Total: {totalField.ValueCurrency.Amount}");
        
    if (document.Fields.TryGetValue("TransactionDate", out DocumentField dateField))
        Console.WriteLine($"Date: {dateField.ValueDate}");
}
```

### 4. Build Custom Model

```csharp
var adminClient = new DocumentIntelligenceAdministrationClient(
    new Uri(endpoint), 
    new AzureKeyCredential(apiKey));

string modelId = "my-custom-model";
Uri blobContainerUri = new Uri("<blob-container-sas-url>");

var blobSource = new BlobContentSource(blobContainerUri);
var options = new BuildDocumentModelOptions(modelId, DocumentBuildMode.Template, blobSource);

Operation<DocumentModelDetails> operation = await adminClient.BuildDocumentModelAsync(
    WaitUntil.Completed, 
    options);

DocumentModelDetails model = operation.Value;

Console.WriteLine($"Model ID: {model.ModelId}");
Console.WriteLine($"Created: {model.CreatedOn}");

foreach (var docType in model.DocumentTypes)
{
    Console.WriteLine($"Document type: {docType.Key}");
    foreach (var field in docType.Value.FieldSchema)
    {
        Console.WriteLine($"  Field: {field.Key}, Confidence: {docType.Value.FieldConfidence[field.Key]}");
    }
}
```

### 5. Build Document Classifier

```csharp
string classifierId = "my-classifier";
Uri blobContainerUri = new Uri("<blob-container-sas-url>");

var sourceA = new BlobContentSource(blobContainerUri) { Prefix = "TypeA/train" };
var sourceB = new BlobContentSource(blobContainerUri) { Prefix = "TypeB/train" };

var docTypes = new Dictionary<string, ClassifierDocumentTypeDetails>()
{
    { "TypeA", new ClassifierDocumentTypeDetails(sourceA) },
    { "TypeB", new ClassifierDocumentTypeDetails(sourceB) }
};

var options = new BuildClassifierOptions(classifierId, docTypes);

Operation<DocumentClassifierDetails> operation = await adminClient.BuildClassifierAsync(
    WaitUntil.Completed, 
    options);

DocumentClassifierDetails classifier = operation.Value;
Console.WriteLine($"Classifier ID: {classifier.ClassifierId}");
```

### 6. Classify Document

```csharp
string classifierId = "my-classifier";
Uri documentUri = new Uri("https://example.com/document.pdf");

var options = new ClassifyDocumentOptions(classifierId, documentUri);

Operation<AnalyzeResult> operation = await client.ClassifyDocumentAsync(
    WaitUntil.Completed, 
    options);

AnalyzeResult result = operation.Value;

foreach (AnalyzedDocument document in result.Documents)
{
    Console.WriteLine($"Document type: {document.DocumentType}, confidence: {document.Confidence}");
}
```

### 7. Manage Models

```csharp
// Get resource details
DocumentIntelligenceResourceDetails resourceDetails = await adminClient.GetResourceDetailsAsync();
Console.WriteLine($"Custom models: {resourceDetails.CustomDocumentModels.Count}/{resourceDetails.CustomDocumentModels.Limit}");

// Get specific model
DocumentModelDetails model = await adminClient.GetModelAsync("my-model-id");
Console.WriteLine($"Model: {model.ModelId}, Created: {model.CreatedOn}");

// List models
await foreach (DocumentModelDetails modelItem in adminClient.GetModelsAsync())
{
    Console.WriteLine($"Model: {modelItem.ModelId}");
}

// Delete model
await adminClient.DeleteModelAsync("my-model-id");
```

## Key Types Reference

| Type | Description |
|------|-------------|
| `DocumentIntelligenceClient` | Main client for analysis |
| `DocumentIntelligenceAdministrationClient` | Model management |
| `AnalyzeResult` | Result of document analysis |
| `AnalyzedDocument` | Single document within result |
| `DocumentField` | Extracted field with value and confidence |
| `DocumentFieldType` | String, Date, Number, Currency, etc. |
| `DocumentPage` | Page info (lines, words, selection marks) |
| `DocumentTable` | Extracted table with cells |
| `DocumentModelDetails` | Custom model metadata |
| `BlobContentSource` | Training data source |

## Build Modes

| Mode | Use Case |
|------|----------|
| `DocumentBuildMode.Template` | Fixed layout documents (forms) |
| `DocumentBuildMode.Neural` | Variable layout documents |

## Best Practices

1. **Use DefaultAzureCredential** for production
2. **Reuse client instances** — clients are thread-safe
3. **Handle long-running operations** — Use `WaitUntil.Completed` for simplicity
4. **Check field confidence** — Always verify `Confidence` property
5. **Use appropriate model** — Prebuilt for common docs, custom for specialized
6. **Use custom subdomain** — Required for Entra ID authentication

## Error Handling

```csharp
using Azure;

try
{
    var operation = await client.AnalyzeDocumentAsync(
        WaitUntil.Completed, 
        "prebuilt-invoice", 
        documentUri);
}
catch (RequestFailedException ex)
{
    Console.WriteLine($"Error: {ex.Status} - {ex.Message}");
}
```

## Related SDKs

| SDK | Purpose | Install |
|-----|---------|---------|
| `Azure.AI.DocumentIntelligence` | Document analysis (this SDK) | `dotnet add package Azure.AI.DocumentIntelligence` |
| `Azure.AI.FormRecognizer` | Legacy SDK (deprecated) | Use DocumentIntelligence instead |

## Reference Links

| Resource | URL |
|----------|-----|
| NuGet Package | https://www.nuget.org/packages/Azure.AI.DocumentIntelligence |
| API Reference | https://learn.microsoft.com/dotnet/api/azure.ai.documentintelligence |
| GitHub Samples | https://github.com/Azure/azure-sdk-for-net/tree/main/sdk/documentintelligence/Azure.AI.DocumentIntelligence/samples |
| Document Intelligence Studio | https://documentintelligence.ai.azure.com/ |
| Prebuilt Models | https://aka.ms/azsdk/formrecognizer/models |