Question

您好我正在尝试比较我的rfid和我的数据库中的两个字符串，我尝试将它们串联起来并且它们是相同的但是当我将它们放在if语句中时它没有显示为真，

这是我的代码，不要介意其他模块只是我目前正在处理的rfid部分。

Arduino的：

#include <SPI.h>
#include <Ethernet.h>
#include <ArduinoHttpClient.h>
#include <Keypad.h>
#include <MFRC522.h>
#include <Servo.h>

/////// RFID Settings ///////
#define SS_PIN 53
#define RST_PIN 10
MFRC522 mfrc522(SS_PIN, RST_PIN);   // Create MFRC522 instance.

/////// Ethernet Settings ///////
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress ip(192, 168, 1, 222);
char serverAddress[] = "192.168.1.51";  // server address
int port = 80;

/////// HttpClient Settings ///////
EthernetClient ethr;
HttpClient client = HttpClient(ethr, serverAddress, port);
String response;
int statusCode = 0;

/////// Keypad Settings ///////
char key[4];
int i = 0;
String pass;
const byte ROWS = 4; // Four rows
const byte COLS = 4; // columnsffff
// Define the Keymap
char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};
// Connect keypad ROW0, ROW1, ROW2 and ROW3 to these Arduino pins.
byte rowPins[ROWS] = {29, 28, 27, 26}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {25, 24, 23, 22}; //connect to the column pinouts of the keypad
Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

/////// Servo Settings ///////
Servo lock; //declares servo

/////// Status Variables & Strings ///////
int rStatus = 0; // RFID Status
int pStatus = 0; // PIN Status
String registeredCard = "160196116163";
String getReq, tag, rfid, pincode;

void setup() {
  /////// Starting Serial ///////
  Serial.begin(9600);
  delay(1000);

  /////// Ethernet Setup ///////
  Serial.println("Initializing Ethernet.");
  Ethernet.begin(mac, ip);
  Serial.println("Connection Success.");
  Serial.println("");
  delay(1000);

  /////// RFID Setup ///////
  Serial.println("Initializing RFID Module.");
  mfrc522.PCD_Init();   // Initiate MFRC522
  Serial.println("RFID Ready.");
  Serial.println("");
  delay(1000);

  /////// Keypad Setup ///////
  Serial.println("Initializing Keypad Module...");
  keypad.addEventListener(keypadEvent); //add an event listener for this keypad
  Serial.println("Keypad Ready.");
  Serial.println("");
  delay(1000);

  Serial.println("Setting up servo motor...");
  lock.attach(13);
  Serial.println("Servo Motor Ready.");
  Serial.println("");
  delay(1000);

  Serial.println("Please tap RFID Card.");
}

void loop() {
  if (rStatus == 0)
  {
    readRFID();
  }
  else if (rStatus == 1)
  {
    keypad.getKey();
  }

  if (rStatus == 1 && pStatus == 1)
  {
    lock.write(5);
    delay(5000);
    lock.write(0);
    rStatus = 0;
    pStatus = 0;

  }
}

/////// Module Methods - RFID ///////
void readRFID()
{
  // Look for new cards
  if ( ! mfrc522.PICC_IsNewCardPresent())
  {
    return;
  }
  // Select one of the cards
  if ( ! mfrc522.PICC_ReadCardSerial())
  {
    return;
  }
  //Show UID on serial monitor
  Serial.print("UID tag : ");
  String content = "";
  //byte letter;
  for (byte i = 0; i < mfrc522.uid.size; i++)
  {
    //Serial.print(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " ");
    //Serial.print(mfrc522.uid.uidByte[i], HEX);
    //content.concat(String(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " "));
    //content.concat(String(mfrc522.uid.uidByte[i], HEX));
    //Serial.print(mfrc522.uid.uidByte[i]);
    content.concat(String(mfrc522.uid.uidByte[i]));
  }
  Serial.println();
  Serial.println(content);
  tag = String(content);
  getRequest();
  Serial.println(rfid);

  if (tag.equals(rfid)) //change here the UID of the card/cards that you want to give access
  {
    Serial.print("Message : ");
    Serial.println("UID Found.");
    Serial.println();
    delay(3000);
    rStatus = 1;
    Serial.println("Please enter 4 digit PIN.");
  }

  else   {
    Serial.println(" Access denied");
    delay(3000);
    rStatus = 0;
  }
}

/////// Module Methods - Keypad ///////
void keypadEvent(KeypadEvent eKey)
{

  switch (keypad.getState())
  {
    case PRESSED:

      key[i] = eKey;
      Serial.print("Enter: ");
      Serial.println(eKey);
      delay(10);
      i++;

      switch (eKey)
      {
        case '#': checkPassword(); delay(1); break;

        case '*': i = 0; delay(1); break;

        default: delay(1);
      }
  }
}

void checkPassword()
{
  pass = "";
  pass.concat(key[0]);
  pass.concat(key[1]);
  pass.concat(key[2]);
  pass.concat(key[3]);

  if (pass == String(pincode))
  {

    Serial.print("Input PIN: ");
    Serial.println(pass);
    Serial.println("Message: PIN Accepted");
    Serial.println("");
    i = 0;
    pStatus = 1;
    delay(10);
  } else
  {
    Serial.println("PIN Denied"); //if passwords wrong keep box locked
    i = 0;
    pStatus = 0;
    delay(10);
  }
}

void getRequest() {
  //Serial.println("Making GET Request");
  getReq.concat("/getTag.php?tag=");
  getReq.concat(tag);
  client.get(getReq);

  // read the status code and body of the response
  //statusCode = client.responseStatusCode();
  response = client.responseBody();
  rfid = response;

  //Serial.print("Response: ");
  //Serial.println(response);

  delay(1000);
}

这是我的.php代码，只显示在数据库

上找到的rfid标记

getTag.php

<?php
   include("connect.php");
   $link=Connection();
   $result= $link->query("SELECT * FROM users WHERE rfid LIKE '".$_GET["tag"]."'"); 
?>
<?php     
   while($row = $result->fetch_array()) {
printf("%s", $row["rfid"]);
   }
   mysqli_free_result($result);
?>

在串行监视器上的结果，它仍显示访问被拒绝。

串口监视器：

Initializing Ethernet.
Connection Success.

Initializing RFID Module.
RFID Ready.

Initializing Keypad Module...
Keypad Ready.

Setting up servo motor...
Servo Motor Ready

Please tap RFID Card.
UID tag : 
160196116163

160196116163
Access denied

我已经尝试过不同类型的比较，比如string1 == string2，strcmp和string1.equals（string2），但仍然是拒绝访问。

但如果我这样做＆gt;＆gt;＆gt;＆gt; if（tag =＆＃34; 160196116163＆＃34;）然后它可以工作。任何人都知道如何使这项工作？

Answer 1

好的，我发现了原因，在我的php文件中，最上面有一个新行，即第1行，我将其删除并立即正常工作。

比较arduino和数据库的字符串

1 个答案: