Problem with substring

Projects Programming
1

I am getting data from one page.

These are the data:

HTTP/1.1 200 OK
Connection: close
Date: Thu, 17 Mar 2016 19:38:06 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
X-Powered-By: PHP/5.4.9
Set-Cookie: PHPSESSID=a9f0n7608v29g9tbkle4ra7n17; path=/
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Content-type: text/html; charset=UTF-8
Content-Length: 94

primeiro_quotefim_mod_ini_mod_ry1=l_ry2=l_ry3=d_ry4=dfim_mod_ini_mod_ry1=lfim_mod_ultimo_quote

I'm using 'primeiro_quote' and 'ultimo_quote' as marks for cutting. When the String received is short it works, but with a big string there is no cut.

This is the code:

#include <EtherCard.h>

// ethernet interface mac address, must be unique on the LAN
static byte mymac[] = { 0x74, 0x69, 0x69, 0x2D, 0x30, 0x31 };

byte Ethernet::buffer[700];
static uint32_t timer;

const char website[] PROGMEM = "arrobaserver.wha.la";
//char website[] PROGMEM = "google.com";
String retorno;

// called when the client request is complete
static void my_callback (byte status, word off, word len) {
  Serial.println(">>>");
  Ethernet::buffer[off + 800] = 0; 
  retorno = ((const char*) Ethernet::buffer + off);
  Serial.println(retorno);
  retorno = retorno.substring(retorno.indexOf("primeiro_quote")+14,retorno.indexOf("ultimo_quote"));
  Serial.println(retorno);

}

void setup () {
  Serial.begin(57600);
  Serial.println("\n[webClient]");

  if (ether.begin(sizeof Ethernet::buffer, mymac) == 0)
    Serial.println( "Failed to access Ethernet controller");
  if (!ether.dhcpSetup())
    Serial.println("DHCP failed");

  ether.printIp("IP:  ", ether.myip);
  ether.printIp("GW:  ", ether.gwip);
  ether.printIp("DNS: ", ether.dnsip);

  if (!ether.dnsLookup(website))
    Serial.println("DNS failed");

  ether.printIp("SRV: ", ether.hisip);
}

void loop () {
  ether.packetLoop(ether.packetReceive());

  if (millis() > timer) {
    timer = millis() + 15000;
    Serial.println();
    Serial.print("<<< REQ ");
    ether.hisport = 8082;//to access  local host
    ether.browseUrl(PSTR("/asp/haroldo/bms/ver.php"), "?predio=1&arduino=1", website, my_callback);
  }
}
2

The data that you have is in a character array. Creating a String instance that wraps that character array is pointless. Making a copy of data from one array to another array, copying only a portion of the array is easy.

The result will be another char array that you can NULL terminate, creating a string. Nothing that the String class does is magic. It is ALL based on string functions. Learn to use those string functions on your string.