I have created with an esp8266 a system with the matrix7219 to write messages and view them on the 4 matrices, via an HTTP connected to my site.
Through PHP I created a text file where each message is inserted with /n to go to the end, the last message is read through this code.
String getlastline(String str)
{
String s="";
int len=str.length();
for (int i=len-2;i>=0;i--)
{
if (str[i]=='
')
{
break;
}
else
{
s=s+str[i];
}
}
String rs="";
for (int i=s.length()-1;i>=0;i--)
{
rs=rs+s[i];
}
return rs;
}
String ricevimessaggio()
{
String lastmessaggio="";
if(WiFi.status()==WL_CONNECTED)
{
HTTPClient http;
String url="http://www.cinesaibai.com/messaggio.txt";
http.begin(url);
http.addHeader("Content-Type","text/plain");
int httpCode=http.GET();
String messaggio=http.getString();
lastmessaggio=getlastline(messaggio);
// Serial.println("il messaggio nuovo è:");
Serial.println(lastmessaggio);
http.end();
}
else
{
lastmessaggio="";
}
return lastmessaggio;
delay(3000);
}
Now I wish I could get the random messages from the txt file.
Can anyone help me, Thanks
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…