Arduino client.read() 保持返回相同的值

Question

Arduino 代码不断返回 bool 1/true

所以我用arduino做了一个RFID阅读器，arduino会读取卡的UID，然后通过GET方法将UID发送给PHP，然后PHP验证/匹配UID与数据库，然后如果UID是与数据库匹配，PHP 应该将 1(bool) 返回给 arduino，它运行良好并且 arduino 将其读取为 1(bool)，但是当我尝试发送不匹配的 UID 时，arduino 将其读取为 1(bool)，应该是0.

这是我的代码

Arduino代码（RFID_uid.ino）

#include <SPI.h>
#include <MFRC522.h>
#include <Ethernet.h>

#define SS_PIN          53
#define RST_PIN         5

MFRC522 rfid(SS_PIN, RST_PIN);


String id_kartu;
bool clientRead;

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
char server[] = "192.168.25.159";
IPAddress ip(192,168,25,20); 
EthernetClient client;

void setup() {
  Serial.begin(9600);
  SPI.begin();
  rfid.PCD_Init();
  if (Ethernet.begin(mac) == 0) {
  Serial.println("Failed to configure Ethernet using DHCP");
  Ethernet.begin(mac, ip);
  }
  if (client.connect(server, 80) || !client.connect(server, 80)) {
    Serial.println("Please Scan Your Card");
  }

  pinMode(LED_BUILTIN, OUTPUT);
  delay(1000);
}

void loop() {
  //Check if there any card on RFID reader
  if (!rfid.PICC_IsNewCardPresent() || !rfid.PICC_ReadCardSerial()) {
    return;
  }
  id_kartu = String(rfid.uid.uidByte[0]) + String(rfid.uid.uidByte[1]) + String(rfid.uid.uidByte[2]) + String(rfid.uid.uidByte[3]);
  rfid.PICC_HaltA();   //Stop reading card
  rfid.PCD_StopCrypto1(); //Stop reading card
  Sending_To_phpmyadmindatabase(); 
  
  delay(2000);
  if (client.available()) {
    clientRead = client.read();
    Serial.println(clientRead);
  }
  

  if(clientRead == 1){
    digitalWrite(LED_BUILTIN, HIGH);
    delay(1500);
  } else {
    digitalWrite(LED_BUILTIN, LOW);
  }
}

void Sending_To_phpmyadmindatabase() {   //CONNECTING WITH MYSQL
   if (client.connect(server, 80)) {
    // Make a HTTP request:
    Serial.print("GET /rfid/tes.php?id=");
    client.print("GET /rfid/tes.php?id=");     //My URL
    Serial.println(id_kartu);
    client.print(id_kartu);
    //client.print(" ");      //SPACE BEFORE HTTP/1.1
    client.print(" HTTP/1.1");
    client.println();
    client.println("Host: 192.168.25.159");
    client.println("Connection: close");
    client.println();
  } else {
    // if didn't get a connection to the server:
    Serial.println("connection failed");
  }

  
 }

PHP 代码 (tes.php)

<?php

    $server = "localhost";
    $username = "****";
    $password = "****";
    $dbname = "****";
    
    
    // Create connection
    $conn = new mysqli($server, $username, $password, $dbname);
    
    // Check connection
    if ($conn->connect_error) {
      die("Connection failed: " . $conn->connect_error);
    }

// Get the QR code from the request
$id_kartu = $_GET["id"];


// Construct the query to check if the QR code matches an authorized student
$query = "SELECT * FROM kartu WHERE id_kartu = '$id_kartu'";

// Execute the query
$result = $conn->query($query);

// Check if the query returned any rows (indicating a match)
if ($result->num_rows > 0) {
  // Return "1" to the Arduino
  return 1;
} else {
  // Return "nothing" to the Arduino
  die;

}



?>

这是串行监视器

Please Scan Your Card
GET /rfid/tes.php?id=1902042134
1

所以 1902042134 UID 在我的数据库中显然不可用，但是 arduino 仍然返回 1(bool) 值，请帮助我