c – 如何从Arduino库中读取数组?

我使用以太网模块使用
Cayenne-Arduino-Library
arduino_uip将数据上传到服务器.我想从
CayenneEthernet.h读取myip []

原版的:

// DHCP with domain
void begin(const char* auth,
    const char* domain = BLYNK_DEFAULT_DOMAIN,
    uint16_t port = BLYNK_DEFAULT_PORT,
    const byte mac[] = _blynkEthernetMac)
{
    BLYNK_LOG("Here we are");// I added this to find this function.
    ...
    IPAddress myip = Ethernet.localIP();
    BLYNK_LOG("My IP: %d.%d.%d.%d", myip[0], myip[1], myip[2], myip[3]);
}

编辑:

// DHCP with domain
int* begin(const char* auth,
    const char* domain = BLYNK_DEFAULT_DOMAIN,
    uint16_t port = BLYNK_DEFAULT_PORT,
    const byte mac[] = _blynkEthernetMac)
{   
    ...
    IPAddress myip = Ethernet.localIP();
    BLYNK_LOG("My IP: %d.%d.%d.%d", myip[0], myip[1], myip[2], myip[3]);
    return myip;
}

Arduino代码:

#define CAYENNE_DEBUG         // Uncomment to show debug messages
#define CAYENNE_PRINT Serial  // Comment this out to disable prints and save space
#include <CayenneDefines.h>
#include <UIPEthernet.h>
#include <BlynkSimpleUIPEthernet.h>
#include <CayenneEthernetClient.h>
#define VIRTUAL_PIN V1
#define VIRTUAL_PIN V0
...
void setup(){
...
  int *A=Cayenne.begin(token);
...
}

void loop(){
...
}

我收到此错误:

error: void value not ignored as it ought to be

题:

如何正确返回数组?

更新:
搜索后,Cayenne.begin()定义于CayenneEthernetClient.h

class CayenneEthernetClient : public CayenneClient
{
public:
    void begin(const char* token, const byte mac[] = NULL)
    {
        BLYNK_LOG("HERE WE ARE 3"); 
        Blynk.begin(token, CAYENNE_DOMAIN, CAYENNE_PORT, GetMACAddress(token, mac));

    }

private:

    const byte* GetMACAddress(const char* token, const byte mac[])
    {
        ...
        return _mac;
    }

    byte _mac[6];
};

CayenneEthernetClient Cayenne;

之后,在BlynkProtocol.h调用此开始函数

private:
    int readHeader(BlynkHeader& hdr);
    uint16_t getNextMsgId();

protected:
    void begin(const char* auth) {
        BLYNK_LOG("HERE WE ARE 2");
        this->authkey = auth;
    }
    bool processInput(void);

之后,这个begin()在BlynkEthernet.h调用

// DHCP with domain
void begin( const char* auth,
            const char* domain = BLYNK_DEFAULT_DOMAIN,
            uint16_t port      = BLYNK_DEFAULT_PORT,
            const byte mac[]   = _blynkEthernetMac)
{
    Base::begin(auth);
    BLYNK_LOG("Getting IP...");
    BLYNK_LOG("HERE WE ARE 1");
    if (!Ethernet.begin((byte*)mac)) {
        BLYNK_FATAL("DHCP Failed!");
    }
    // give the Ethernet shield a second to initialize:
    ::delay(1000);
    this->conn.begin(domain, port);
    IPAddress myip = Ethernet.localIP();
    BLYNK_LOG("My IP: %d.%d.%d.%d", myip[0], myip[1], myip[2], myip[3]);

}

这个begin()最终在BlynkArduinoClient.h被调用

void begin(const char* d, uint16_t p) {
    BLYNK_LOG("HERE WE ARE 9");
    domain = d;
    port = p;
}

串行监视器上的输出:

06007

最佳答案 我认为修改代码甚至库的API都不是一个好主意.

我的方法是获取IP地址的方式与Cayenne库相同:调用Ethernet.localIP():

void setup() {
    Cayenne.begin(token);
    IPAddress myip = Ethernet.localIP();
}

P.S.:错误

void value not ignored as it ought to be

可能是因为你只修改了Cayenne类中三个重写的begin()方法之一.

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