Question

我正在检查一个数字的文本文件（使用HTTP请求）。我想在每次更改时跟踪这个数字，所以我在字符数组中收集HTTP响应并将其与先前存储的计数进行比较（尝试使用int，现在尝试使用字符数组）但它不会似乎存储结果。 lastCount是一个全局变量，此函数用于检查和存储新计数：

boolean checkCount()
{
  char currentLine[15];
  int index=0;
  if (client.connected())
  {
    Serial.println("Connected. Checking for availabilty of client...");
    if (client.available())
    {
      Serial.println("Client is available! Trying to read from client...");
      // read incoming bytes:

      if(client.find("\r\n\r\n"))
      {

      char inChar;
      while(inChar=client.read())
      {
        if(inChar==-1) break;
          currentLine[index] = inChar; //read in all characters of count
          currentLine[index+1] = '\0';
          index++;
        Serial.print("\n\nCurrent count count: ");
        Serial.print(currentLine);
        Serial.print("\n\n");
      }
      if(strcmp(currentLine,lastCount)!=0) //not equal
      {
        Serial.println("NOT EQUAL TO LAST COUNT");
        Serial.print("last count: "); //test output
        Serial.print(lastCount);
        Serial.print("current count: ");
        Serial.println(currentLine);

        strcpy(lastCount, currentLine);//, sizeof(lastCount));

        Serial.println("BLINKING LED");
        blink(3);
      }
      else
      {
        Serial.println("EQUAL TO LAST COUNT");
        Serial.println("NOT BLINKING.");
      }

      delay(5000); //delay 5 seconds (don't kill server)
      return true;
     }
     else
     {
       Serial.println("newlines not found - error with request");
       return false;
     }
    }
    else
    {
      Serial.println("count not available");
      return false;
    }
  }
  //...
}

Answer 1

请参阅以下代码：

你应该把这个'\ 0'放在数组中字符串的末尾。

currentLine [index + 1] ='\ 0';应该从“while循环”中调用此行。否则strcmp总是只从“currentLine”获得一个字符。

请在存储输入时注意字符串缓冲区的数组长度

while(inChar=client.read())
{         
    currentLine[index++] = inChar; //read in all characters of count
}
currentLine[index] = '\0';

if(strcmp(currentLine,lastCount)!=0) //no

字符数组不使用strcpy进行复制

1 个答案: