的版本 4 (V4) 适用于 .NET 的 AWS SDK 已经发布！

有关重大更改和迁移应用程序的信息，请参阅[迁移主题](https://docs.aws.amazon.com/sdk-for-net/v4/developer-guide/net-dg-v4.html)。

 [https://docs.aws.amazon.com/sdk-for-net/v4/developer-guide/net-dg-v4.html](https://docs.aws.amazon.com/sdk-for-net/v4/developer-guide/net-dg-v4.html)

本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

# 通过 JSON 创建 IAM 托管式策略
<a name="iam-policies-create-json"></a>

此示例向您展示如何使用根据给定的 JSON [策略文档创建 IAM 托管](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_managed-vs-inline.html#aws-managed-policies)策略。 适用于 .NET 的 AWS SDK 该应用程序创建 IAM 客户端对象，从文件中读取策略文档，然后创建策略。

**注意**  
有关 JSON 格式的示例策略文档，请参阅本主题末尾的[其它注意事项](#iam-policies-create-json-additional)。

以下各节提供了此示例的片段。此后显示了[该示例的完整代码](#iam-policies-create-json-complete-code)，并且可以按原样构建和运行。

**Topics**
+ [创建策略](#iam-policies-create-json-create)
+ [完整代码](#iam-policies-create-json-complete-code)
+ [其他注意事项](#iam-policies-create-json-additional)

## 创建策略
<a name="iam-policies-create-json-create"></a>

以下代码片段使用给定名称和策略文档创建一个 IAM 托管式策略。

[本主题末尾](#iam-policies-create-json-complete-code)的示例显示了此片段的使用情况。

```
    //
    // 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)});
    }
```

## 完整代码
<a name="iam-policies-create-json-complete-code"></a>

本部分显示了本示例的相关参考和完整代码。

### SDK 参考
<a name="w2aac19c15c23c21c17b5b1"></a>

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

编程元素：
+ 命名空间 [Amazon。 IdentityManagement](https://docs.aws.amazon.com/sdkfornet/v4/apidocs/items/IAM/NIAM.html)

  班级 [AmazonIdentityManagementServiceClient](https://docs.aws.amazon.com/sdkfornet/v4/apidocs/items/IAM/TIAMServiceClient.html)
+ 命名空间 [Amazon。 IdentityManagement.Model](https://docs.aws.amazon.com/sdkfornet/v4/apidocs/items/IAM/NIAMModel.html)

  班级 [CreatePolicyRequest](https://docs.aws.amazon.com/sdkfornet/v4/apidocs/items/IAM/TCreatePolicyRequest.html)

  班级 [CreatePolicyResponse](https://docs.aws.amazon.com/sdkfornet/v4/apidocs/items/IAM/TCreatePolicyResponse.html)

### 代码
<a name="w2aac19c15c23c21c17b7b1"></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);
    }
  }

}
```

## 其他注意事项
<a name="iam-policies-create-json-additional"></a>
+ 以下是示例策略文档，您可以将其复制到 JSON 文件中并用作此应用程序的输入：

------
#### [ 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": "*"
      }
    ]
  }
  ```

------
+ 您可以通过查看 [IAM 控制台](https://console.aws.amazon.com/iam/home#/policies)来验证策略是否已创建。使用**筛选策略**下拉菜单，选择**客户托管**。在您不再需要策略时将其删除。
+  有关创建策略的更多信息，请参阅 [IAM 用户指南](https://docs.aws.amazon.com/IAM/latest/UserGuide/)中的[创建 IAM 策略](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_create.html)和 [IAM JSON 策略参考](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies.html)