適用於 .NET 的 AWS SDK V3 已進入維護模式。

我們建議您遷移至 [適用於 .NET 的 AWS SDK V4](https://docs.aws.amazon.com/sdk-for-net/v4/developer-guide/welcome.html)。如需如何遷移的其他詳細資訊和資訊，請參閱我們的[維護模式公告](https://aws.amazon.com/blogs/developer/aws-sdk-for-net-v3-maintenance-mode-announcement/)。

本文為英文版的機器翻譯版本，如內容有任何歧義或不一致之處，概以英文版為準。

# 從 JSON 建立 IAM 受管政策
<a name="iam-policies-create-json"></a>

此範例說明如何使用 從 JSON 中的指定政策文件中 適用於 .NET 的 AWS SDK 建立 [IAM 受](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_managed-vs-inline.html#aws-managed-policies)管政策。應用程式會建立 IAM 用戶端物件、從 檔案讀取政策文件，然後建立政策。

**注意**  
如需 JSON 中的範例政策文件，請參閱本主題結尾[的其他考量](#iam-policies-create-json-additional)事項。

下列各節提供此範例的程式碼片段。之後會顯示[範例的完整程式碼](#iam-policies-create-json-complete-code)，並可依原樣建置和執行。

**Topics**
+ [建立政策](#iam-policies-create-json-create)
+ [完成程式碼](#iam-policies-create-json-complete-code)
+ [其他考量](#iam-policies-create-json-additional)

## 建立政策
<a name="iam-policies-create-json-create"></a>

下列程式碼片段會建立具有指定名稱和政策文件的 IAM 受管政策。

[本主題結尾](#iam-policies-create-json-complete-code)的範例顯示此程式碼片段正在使用中。

```
    //
    // Method to create an IAM policy from a JSON file
    private static async Task<CreatePolicyResponse> CreateManagedPolicy(
      IAmazonIdentityManagementService iamClient, string policyName, string jsonFilename)
    {
      return await iamClient.CreatePolicyAsync(new CreatePolicyRequest{
        PolicyName = policyName,
        PolicyDocument = File.ReadAllText(jsonFilename)});
    }
```

## 完成程式碼
<a name="iam-policies-create-json-complete-code"></a>

本節顯示此範例的相關參考和完整程式碼。

### 開發套件參考
<a name="w2aac19c15c19c21c17b5b1"></a>

NuGet 套件：
+ [AWSSDK.IdentityManagement](https://www.nuget.org/packages/AWSSDK.IdentityManagement)

程式設計元素：
+ 命名空間 [Amazon.IdentityManagement](https://docs.aws.amazon.com/sdkfornet/v3/apidocs/items/IAM/NIAM.html)

  [AmazonIdentityManagementServiceClient](https://docs.aws.amazon.com/sdkfornet/v3/apidocs/items/IAM/TIAMServiceClient.html) 類別
+ 命名空間 [Amazon.IdentityManagement.Model](https://docs.aws.amazon.com/sdkfornet/v3/apidocs/items/IAM/NIAMModel.html)

  類別 [CreatePolicyRequest](https://docs.aws.amazon.com/sdkfornet/v3/apidocs/items/IAM/TCreatePolicyRequest.html)

  類別 [CreatePolicyResponse](https://docs.aws.amazon.com/sdkfornet/v3/apidocs/items/IAM/TCreatePolicyResponse.html)

### 程式碼
<a name="w2aac19c15c19c21c17b7b1"></a>

```
using System;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using Amazon.IdentityManagement;
using Amazon.IdentityManagement.Model;

namespace IamCreatePolicyFromJson
{
  // = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
  // Class to create an IAM policy with a given policy document
  class Program
  {
    private const int MaxArgs = 2;

    static async Task Main(string[] args)
    {
      // Parse the command line and show help if necessary
      var parsedArgs = CommandLine.Parse(args);
      if((parsedArgs.Count == 0) || (parsedArgs.Count > MaxArgs))
      {
        PrintHelp();
        return;
      }

      // Get the application arguments from the parsed list
      string policyName =
        CommandLine.GetArgument(parsedArgs, null, "-p", "--policy-name");
      string policyFilename =
        CommandLine.GetArgument(parsedArgs, null, "-j", "--json-filename");
      if(   string.IsNullOrEmpty(policyName)
         || (string.IsNullOrEmpty(policyFilename) || !policyFilename.EndsWith(".json")))
        CommandLine.ErrorExit(
          "\nOne or more of the required arguments is missing or incorrect." +
          "\nRun the command with no arguments to see help.");

      // Create an IAM service client
      var iamClient = new AmazonIdentityManagementServiceClient();

      // Create the new policy
      var response = await CreateManagedPolicy(iamClient, policyName, policyFilename);
      Console.WriteLine($"\nPolicy {response.Policy.PolicyName} has been created.");
      Console.WriteLine($"  Arn: {response.Policy.Arn}");
    }


    //
    // Method to create an IAM policy from a JSON file
    private static async Task<CreatePolicyResponse> CreateManagedPolicy(
      IAmazonIdentityManagementService iamClient, string policyName, string jsonFilename)
    {
      return await iamClient.CreatePolicyAsync(new CreatePolicyRequest{
        PolicyName = policyName,
        PolicyDocument = File.ReadAllText(jsonFilename)});
    }


    //
    // Command-line help
    private static void PrintHelp()
    {
      Console.WriteLine(
        "\nUsage: IamCreatePolicyFromJson -p <policy-name> -j <json-filename>" +
        "\n  -p, --policy-name: The name you want the new policy to have." +
        "\n  -j, --json-filename: The name of the JSON file with the policy document.");
    }
  }


  // = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
  // Class that represents a command line on the console or terminal.
  // (This is the same for all examples. When you have seen it once, you can ignore it.)
  static class CommandLine
  {
    //
    // Method to parse a command line of the form: "--key value" or "-k value".
    //
    // Parameters:
    // - args: The command-line arguments passed into the application by the system.
    //
    // Returns:
    // A Dictionary with string Keys and Values.
    //
    // If a key is found without a matching value, Dictionary.Value is set to the key
    //  (including the dashes).
    // If a value is found without a matching key, Dictionary.Key is set to "--NoKeyN",
    //  where "N" represents sequential numbers.
    public static Dictionary<string,string> Parse(string[] args)
    {
      var parsedArgs = new Dictionary<string,string>();
      int i = 0, n = 0;
      while(i < args.Length)
      {
        // If the first argument in this iteration starts with a dash it's an option.
        if(args[i].StartsWith("-"))
        {
          var key = args[i++];
          var value = key;

          // Check to see if there's a value that goes with this option?
          if((i < args.Length) && (!args[i].StartsWith("-"))) value = args[i++];
          parsedArgs.Add(key, value);
        }

        // If the first argument in this iteration doesn't start with a dash, it's a value
        else
        {
          parsedArgs.Add("--NoKey" + n.ToString(), args[i++]);
          n++;
        }
      }

      return parsedArgs;
    }

    //
    // Method to get an argument from the parsed command-line arguments
    //
    // Parameters:
    // - parsedArgs: The Dictionary object returned from the Parse() method (shown above).
    // - defaultValue: The default string to return if the specified key isn't in parsedArgs.
    // - keys: An array of keys to look for in parsedArgs.
    public static string GetArgument(
      Dictionary<string,string> parsedArgs, string defaultReturn, params string[] keys)
    {
      string retval = null;
      foreach(var key in keys)
        if(parsedArgs.TryGetValue(key, out retval)) break;
      return retval ?? defaultReturn;
    }

    //
    // Method to exit the application with an error.
    public static void ErrorExit(string msg, int code=1)
    {
      Console.WriteLine("\nError");
      Console.WriteLine(msg);
      Environment.Exit(code);
    }
  }

}
```

## 其他考量
<a name="iam-policies-create-json-additional"></a>
+ 以下是您可以複製到 JSON 檔案並用作此應用程式輸入的範例政策文件：

------
#### [ JSON ]

****  

  ```
  {
    "Version":"2012-10-17",		 	 	 
    "Id"  : "DotnetTutorialPolicy",
    "Statement" : [
      {
        "Sid" : "DotnetTutorialPolicyS3",
        "Effect" : "Allow",
        "Action" : [
          "s3:Get*",
          "s3:List*"
        ],
        "Resource" : "*"
      },
      {
        "Sid" : "DotnetTutorialPolicyPolly",
        "Effect": "Allow",
        "Action": [
          "polly:DescribeVoices",
          "polly:SynthesizeSpeech"
        ],
        "Resource": "*"
      }
    ]
  }
  ```

------
+ 您可以在 [IAM 主控台](https://console.aws.amazon.com/iam/home#/policies)中查看政策是否已建立。在**篩選政策**下拉式清單中，選取**客戶受管**。當您不再需要政策時，請將其刪除。
+  如需政策建立的詳細資訊，請參閱《[IAM 使用者指南》中的建立](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_create.html) [IAM 政策和 IAM](https://docs.aws.amazon.com/IAM/latest/UserGuide/) [JSON 政策參考](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies.html)