要在ASP.NET Core中保持与ESP32的连接,你可以使用WebSocket来实现。下面是一个示例代码:
首先,在ASP.NET Core项目中创建一个WebSocket中间件。在Startup.cs文件的Configure方法中添加以下代码:
app.UseWebSockets();
app.Use(async (context, next) =>
{
if (context.Request.Path == "/ws")
{
if (context.WebSockets.IsWebSocketRequest)
{
WebSocket webSocket = await context.WebSockets.AcceptWebSocketAsync();
await HandleWebSocket(webSocket);
}
else
{
context.Response.StatusCode = 400;
}
}
else
{
await next();
}
});
接下来,在HandleWebSocket方法中处理WebSocket连接和消息:
private async Task HandleWebSocket(WebSocket webSocket)
{
var buffer = new byte[1024];
WebSocketReceiveResult result = await webSocket.ReceiveAsync(new ArraySegment(buffer), CancellationToken.None);
while (!result.CloseStatus.HasValue)
{
string message = Encoding.UTF8.GetString(buffer, 0, result.Count);
// 处理接收到的消息
result = await webSocket.ReceiveAsync(new ArraySegment(buffer), CancellationToken.None);
}
await webSocket.CloseAsync(result.CloseStatus.Value, result.CloseStatusDescription, CancellationToken.None);
}
在ESP32设备上,你需要使用Arduino IDE和ESPAsyncWebServer库来创建一个WebSocket客户端。以下是一个示例代码:
#include
#include
#include
const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";
const char* serverIP = "your_ASPNETCore_server_IP";
const int serverPort = 80;
const char* websocketPath = "/ws";
WiFiClient client;
AsyncWebSocketClient *webSocketClient;
void setup() {
Serial.begin(115200);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(1000);
Serial.println("Connecting to WiFi...");
}
if (client.connect(serverIP, serverPort)) {
Serial.println("Connected to server");
webSocketClient = new AsyncWebSocketClient(&client);
webSocketClient->onMessage(onWebSocketMessage);
webSocketClient->onEvent(onWebSocketEvent);
String handshake = "GET " + String(websocketPath) + " HTTP/1.1\r\n" +
"Host: " + String(serverIP) + ":" + String(serverPort) + "\r\n" +
"Connection: Upgrade\r\n" +
"Upgrade: websocket\r\n" +
"Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\n" +
"Sec-WebSocket-Version: 13\r\n\r\n";
client.print(handshake);
} else {
Serial.println("Failed to connect to server");
}
}
void loop() {
// 处理其他任务
}
void onWebSocketMessage(void *arg, uint8_t *data, size_t len) {
// 处理接收到的消息
}
void onWebSocketEvent(void *arg, asyncWebSocketClientEvent_t *event) {
if (event->type == WS_EVT_CONNECT) {
Serial.println("WebSocket connected");
} else if (event->type == WS_EVT_DISCONNECT) {
Serial.println("WebSocket disconnected");
}
}
确保将代码中的"your_SSID"、"your_PASSWORD"、"your_ASPNETCore_server_IP"替换为你的WiFi信息和ASP.NET Core服务器的IP地址。
这样,ASP.NET Core服务器和ESP32设备之间就建立了WebSocket连接,并可以通过发送和接收消息来保持连接。