【发布时间】：2021-10-22 20:01:26
【问题描述】：
各位程序员大家好！我正在做一个小项目——它是关于通过 PHP 脚本将数据从 arduino 传感器发送到数据库。我有自己的网站作为主机，我的 php 脚本使用 GET 方法发送数据。我对其进行了多次测试，如果我将原始数字放入 sql 查询（数据库正在获得记录），它会正确发送数据，但是当我想将 arduino 中的变量放入查询时问题就开始了 - 它在表中放入“0” .我看了很多教程并在这里寻找解决方案 - 无济于事。这是我的 PHP 脚本：
<html>
<body>
<?php
require_once "sql_connect.php";
$connect = @mysqli_connect($dbhost,$dbuser,$dbpass,$dbname);
if(!$connect){
echo "Error: " . mysqli_connect_error();
exit();
}
echo "Connection Success!<br><br>";
$waterlevel = $_GET["waterlevel"];
echo $waterlevel;
$query = "INSERT INTO waterLevelTable (waterlevel) VALUES ('".$waterlevel."')"; //sends 0
//$query = "INSERT INTO waterLevelTable (waterlevel) VALUES ('20')"; sends 20 to table
$result = mysqli_query($connect,$query);
echo "Insertion Success!<br>";
?>
</body>
</html>
sql_connect.php 是我拥有凭据的地方。
现在进入 Arduino 代码。我从arduino示例中“借用”了代码片段，DHCPAdressPrint连接到互联网，为水传感器编写代码，然后尝试通过GET方法将传感器值发送到数据库。这就是我挣扎的地方......这是代码：
#include <SPI.h>
#include <Ethernet.h>
#define POWER_PIN_WATER_SENS 7
#define SIGNAL_PIN_WATER_SENS A5
#define SOUND_PIN A0
byte mac[] = {0x00, 0xAA, 0xBB, 0xCC, 0xDE, 0x02};
int waterLevel = 0;
String waterLevelString;
EthernetClient client;
void setup() {
Serial.begin(9600);
pinMode(POWER_PIN_WATER_SENS,OUTPUT);
digitalWrite(POWER_PIN_WATER_SENS, LOW);
Serial.println("Initialize Ethernet with DHCP:");
if (Ethernet.begin(mac) == 0) {
Serial.println("Failed to configure Ethernet using DHCP");
if (Ethernet.hardwareStatus() == EthernetNoHardware) {
Serial.println("Ethernet shield was not found. Sorry, can't run without hardware. :(");
} else if (Ethernet.linkStatus() == LinkOFF) {
Serial.println("Ethernet cable is not connected.");
}
while (true) {
delay(1);
}
}
Serial.print("My IP address: ");
Serial.println(Ethernet.localIP());
}
void loop() {
switch (Ethernet.maintain()) {
case 1:
//renewed fail
Serial.println("Error: renewed fail");
break;
case 2:
//renewed success
Serial.println("Renewed success");
//print your local IP address:
Serial.print("My IP address: ");
Serial.println(Ethernet.localIP());
break;
case 3:
//rebind fail
Serial.println("Error: rebind fail");
break;
case 4:
//rebind success
Serial.println("Rebind success");
//print your local IP address:
Serial.print("My IP address: ");
Serial.println(Ethernet.localIP());
break;
default:
//nothing happened
break;
}
digitalWrite(POWER_PIN_WATER_SENS, HIGH);
delay(100);
waterLevel = analogRead(SIGNAL_PIN_WATER_SENS);
digitalWrite(POWER_PIN_WATER_SENS, LOW);
Serial.print("Water: ");
waterLevel = 1; //debug value
Serial.println(waterLevel);
waterLevelString = "waterlevel=" + (String)waterLevel;
if (client.connect("<snip>", 80)) {
client.print("GET /arduino_connect_to_db.php HTTP/1.1");
client.println("Host: <snip>");
client.println("Content-Type: application/x-www-form-urlencoded");
client.print("Content-Length: ");
client.println(waterLevelString.length());
client.println();
client.print(waterLevelString);
}
if (client.connected()) {
client.stop();
}
delay(3000);
}
我认为问题出在 arduino 和 php 脚本之间的连接上 - 我不知道有错误。你能帮我找到它并给出解决方案吗？
【问题讨论】：
-
我认为您可以将水位字符串添加到
GET /arduino_to_db.php行并删除有关 Content-Type 和 Content-Length 的标题。 -
Content-Type: application/x-www-form-urlencoded是 POST 请求所必需的，而不是 GET 请求 -
您的脚本对于 sql 注入来说是易受攻击的，因此请仅使用 带参数的准备好的语句参见stackoverflow.com/questions/60174/…
-
... 或者只是将您的变量转换为 int。这个脚本对于任何长期解决方案来说都太简单了。