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发送 Amazon SMS 消息
此示例向您展示如何使用 AWS SDK for .NET 向 Amazon SQS 队列发送消息,您可以通过编程方式或使用 Amazon SQS 控制台
此示例和下一个有关接收消息的示例可以一起使用,以查看 Amazon SQS 中的消息流。
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,并且可以按原样构建和运行。
发送消息
以下代码片段将消息发送到由给定队列 URL 标识的队列。
本主题末尾的示例显示了此片段的使用情况。
// // Method to put a message on a queue // Could be expanded to include message attributes, etc., in a SendMessageRequest private static async Task SendMessage( IAmazonSQS sqsClient, string qUrl, string messageBody) { SendMessageResponse responseSendMsg = await sqsClient.SendMessageAsync(qUrl, messageBody); Console.WriteLine($"Message added to queue\n {qUrl}"); Console.WriteLine($"HttpStatusCode: {responseSendMsg.HttpStatusCode}"); }
发送一批消息
以下代码片段向由给定队列 URL 标识的队列发送一批消息。
本主题末尾的示例显示了此片段的使用情况。
// // Method to put a batch of messages on a queue // Could be expanded to include message attributes, etc., // in the SendMessageBatchRequestEntry objects private static async Task SendMessageBatch( IAmazonSQS sqsClient, string qUrl, List<SendMessageBatchRequestEntry> messages) { Console.WriteLine($"\nSending a batch of messages to queue\n {qUrl}"); SendMessageBatchResponse responseSendBatch = await sqsClient.SendMessageBatchAsync(qUrl, messages); // Could test responseSendBatch.Failed here foreach(SendMessageBatchResultEntry entry in responseSendBatch.Successful) Console.WriteLine($"Message {entry.Id} successfully queued."); }
从队列中删除所有消息
以下代码片段删除了来自由给定队列 URL 标识的队列的所有消息。这也称为清除队列。
本主题末尾的示例显示了此片段的使用情况。
// // Method to delete all messages from the queue private static async Task DeleteAllMessages(IAmazonSQS sqsClient, string qUrl) { Console.WriteLine($"\nPurging messages from queue\n {qUrl}..."); PurgeQueueResponse responsePurge = await sqsClient.PurgeQueueAsync(qUrl); Console.WriteLine($"HttpStatusCode: {responsePurge.HttpStatusCode}"); }
完整代码
本部分显示了本示例的相关参考和完整代码。
NuGet 程序包:
编程元素:
using System; using System.Collections.Generic; using System.Threading.Tasks; using Amazon.SQS; using Amazon.SQS.Model; namespace SQSSendMessages { // = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = // Class to send messages to a queue class Program { // Some example messages to send to the queue private const string JsonMessage = "{\"product\":[{\"name\":\"Product A\",\"price\": \"32\"},{\"name\": \"Product B\",\"price\": \"27\"}]}"; private const string XmlMessage = "<products><product name=\"Product A\" price=\"32\" /><product name=\"Product B\" price=\"27\" /></products>"; private const string CustomMessage = "||product|Product A|32||product|Product B|27||"; private const string TextMessage = "Just a plain text message."; static async Task Main(string[] args) { // Do some checks on the command-line if(args.Length == 0) { Console.WriteLine("\nUsage: SQSSendMessages queue_url"); Console.WriteLine(" queue_url - The URL of an existing SQS queue."); return; } if(!args[0].StartsWith("https://sqs.")) { Console.WriteLine("\nThe command-line argument isn't a queue URL:"); Console.WriteLine($"{args[0]}"); return; } // Create the Amazon SQS client var sqsClient = new AmazonSQSClient(); // (could verify that the queue exists) // Send some example messages to the given queue // A single message await SendMessage(sqsClient, args[0], JsonMessage); // A batch of messages var batchMessages = new List<SendMessageBatchRequestEntry>{ new SendMessageBatchRequestEntry("xmlMsg", XmlMessage), new SendMessageBatchRequestEntry("customeMsg", CustomMessage), new SendMessageBatchRequestEntry("textMsg", TextMessage)}; await SendMessageBatch(sqsClient, args[0], batchMessages); // Let the user send their own messages or quit await InteractWithUser(sqsClient, args[0]); // Delete all messages that are still in the queue await DeleteAllMessages(sqsClient, args[0]); } // // Method to put a message on a queue // Could be expanded to include message attributes, etc., in a SendMessageRequest private static async Task SendMessage( IAmazonSQS sqsClient, string qUrl, string messageBody) { SendMessageResponse responseSendMsg = await sqsClient.SendMessageAsync(qUrl, messageBody); Console.WriteLine($"Message added to queue\n {qUrl}"); Console.WriteLine($"HttpStatusCode: {responseSendMsg.HttpStatusCode}"); } // // Method to put a batch of messages on a queue // Could be expanded to include message attributes, etc., // in the SendMessageBatchRequestEntry objects private static async Task SendMessageBatch( IAmazonSQS sqsClient, string qUrl, List<SendMessageBatchRequestEntry> messages) { Console.WriteLine($"\nSending a batch of messages to queue\n {qUrl}"); SendMessageBatchResponse responseSendBatch = await sqsClient.SendMessageBatchAsync(qUrl, messages); // Could test responseSendBatch.Failed here foreach(SendMessageBatchResultEntry entry in responseSendBatch.Successful) Console.WriteLine($"Message {entry.Id} successfully queued."); } // // Method to get input from the user // They can provide messages to put in the queue or exit the application private static async Task InteractWithUser(IAmazonSQS sqsClient, string qUrl) { string response; while (true) { // Get the user's input Console.WriteLine("\nType a message for the queue or \"exit\" to quit:"); response = Console.ReadLine(); if(response.ToLower() == "exit") break; // Put the user's message in the queue await SendMessage(sqsClient, qUrl, response); } } // // Method to delete all messages from the queue private static async Task DeleteAllMessages(IAmazonSQS sqsClient, string qUrl) { Console.WriteLine($"\nPurging messages from queue\n {qUrl}..."); PurgeQueueResponse responsePurge = await sqsClient.PurgeQueueAsync(qUrl); Console.WriteLine($"HttpStatusCode: {responsePurge.HttpStatusCode}"); } } }
其他注意事项
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有关消息的各种限制(包括允许的字符)的信息,请参阅 Amazon Simple Queue Service 开发人员指南中与消息相关的配额部分。
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消息会一直保留在队列中,直到被删除或队列被清除。当应用程序收到一条消息时,即使它仍然存在于队列中,它也不会出现在队列中。有关可见性超时的更多信息,请参阅 Amazon SQS 可见性超时。
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除了消息正文外,您还可以为消息添加属性。有关更多信息,请参阅消息元数据。