Question

我试图通过首先将整个文本发送到找到其长度的函数并使用AT + CIPSEND = length来到这里以稍后打开TCP端口来读取某些文本的传递数据到服务器上。在我向响应数据添加一些额外信息之前，一切正常。 我怀疑char限制，但即使调试了几个小时也找不到原因。

Serial.println（）没有显示任何输出，字符串连接似乎不健康。问题是文本没有被传递，因此CIPSEND不起作用。相应的代码部分及其输出如下所示。

void sendHTTPResponse(int connectionId, String content) {
  Serial.println("SENDHTTPRESPONSE1: " + content);

  // build HTTP response
  String httpResponse;
  String httpHeader;
  // HTTP Header
  httpHeader = "HTTP/1.1 200 OK\r\nContent-Type: text/html; charset=UTF-8\r\n";
  httpHeader += "Content-Length: ";
  httpHeader += content.length();
  httpHeader += "\r\n";
  httpHeader += "Connection: close\r\n\r\n";
  Serial.println("SENDHTTPRESPONSE2: " + httpHeader);
  httpResponse = httpHeader + content + " "; // There is a bug in this code: the last character of "content" is not sent, I cheated by adding this extra space
  Serial.println("HTTPRESPONSE3: " + httpResponse);
  sendCIPData(connectionId, httpResponse);
}

串行监视器输出。 HTTPRESPONSE3似乎是空的？

SENDHTTPRESPONSE1: {"data":[{"id":"100"}]}{"data":[{"id":"100"}]}{"data":[{"id":"100"}]}{"data":[{"id":"100"}]}
SENDHTTPRESPONSE2: HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8
Content-Length: 92
Connection: close



DATA LENGTH: 



======================================================
Executing command: AT+CIPSEND=0,0


HTTP/1.1
CoAT+CIPSEND=0,0

提前致谢。

Answer 1

这个答案实际上并没有解决你的问题。以我为借口，我没有 Arduino ，所以我无法重现你的问题。：）

但是，由于您使用＆＃34;字符串连接＆＃34; 样式，我认为您可能会受益于使用此处发布的源代码（前提是您的项目有空间）它）

这是我两年前写的 print 库周围的一个小的 c ++ - 样式 包装。它会让你写这样的东西：

io::cout << "This is a beautiful message!\n"
         << io::setprecision(3) << some_float << "\n"
         << io::setbase(BIN) << some_int << io::endl;

默认情况下，库提供io::cout，通过常规Serial进行打印。您可以将此库与实现打印接口的任何对象挂钩，例如串行和软件序列。

与您现在所做的不同之处在于使用＆＃34;＆lt;＆lt;＆＃34;您将获得与＆＃34; +＆＃34;相同的干净代码风格，但您不需要创建临时String。一切都立即下放到输出缓冲区打印出来。因此，您不应该遇到与您现在遇到的问题相同的问题。换句话说，这确实是@Olaf在评论中提出的，但是以一种奇特的方式。 ;）

注意：您可能需要修复 test-iocout.ino 文件中的包含以适合您的项目。

cout.h

#ifndef __COUT_H__
#define __COUT_H__

#include <Arduino.h>

namespace io {

/**
 * marker to end a message
 * (prints newline)
 */
struct Endl {};
const Endl endl = Endl();

/**
 * marker to modify way in which numbers are
 * printed on output stream
 */
struct setbase {
    uint8_t base;
    setbase(uint8_t v = DEC): base(v) {}
};

/**
 * marker to modify number of digits of doubles
 * printed on output stream
 */
struct setprecision {
    uint8_t precision;
    setprecision(uint8_t v = 2): precision(v) {}
};


/**
 * class out
 *
 * Provides a C++-like interface for printing stuff on
 * an output Stream, e.g. Serial, SoftwareSerial objects
 * Assumes a separated Stream initialization handling
 */
class out {
public:

    out(Print& print = Serial, uint8_t fmt = DEC, uint8_t dgt = 2);
    out(const out& other);
    out& operator =(const out& other);
    virtual ~out();

    inline out& operator<<(const String& msg)
    {
        __print.print(msg);
        return *this;
    };

    inline out& operator<<(const char msg[])
    {
        __print.print(msg);
        return *this;
    };

    inline out& operator<<(char c)
    {
        __print.print(c);
        return *this;
    };

    inline out& operator<<(unsigned char uc)
    {
        __print.print(uc, __base);
        return *this;
    };

    inline out& operator<<(int n)
    {
        __print.print(n, __base);
        return *this;
    };

    inline out& operator<<(unsigned int un)
    {
        __print.print(un, __base);
        return *this;
    };

    inline out& operator<<(long l)
    {
        __print.print(l, __base);
        return *this;
    };

    inline out& operator<<(unsigned long ul)
    {
        __print.print(ul, __base);
        return *this;
    };

    inline out& operator<<(double d)
    {
        __print.print(d, __precision);
        return *this;
    };

    inline out& operator<<(const __FlashStringHelper *fsh)
    {
        __print.print(fsh);
        return *this;
    };

    inline out& operator<<(const Printable& pr)
    {
        __print.print(pr);
        return *this;
    };

    inline out& operator<<(const Endl& el)
    {
        __print.println("");
        __base = DEC;
        __precision = 2;
        return *this;
    };

    inline out& operator<<(const setbase& p)
    {
        __base = p.base;
        return *this;
    };

    inline out& operator<<(const setprecision& p)
    {
        __precision = p.precision;
        return *this;
    };

    inline int getWriteError()
    {
        return __print.getWriteError();
    };

    inline void clearWriteError()
    {
        __print.clearWriteError();
    };

private:
    Print& __print;
    ///< output stream, must be separately initalized
    uint8_t __base;
    ///< base with which print numerical data
    uint8_t __precision;
    ///< number of fractional digits of float/double values
};

/**
 * Global io::cout object
 */
extern out cout;

} /* namespace io */

#endif

cout.cpp

#include "cout.h"

namespace io {

out cout;

out::out(Print& print, uint8_t fmt, uint8_t dgt):
    __print(print), __base(fmt),
    __precision(dgt)
{
    // nothing to do
};

out::out(const out& other):
    __print(other.__print),
    __base(other.__base),
    __precision(other.__precision)
{
    // nothing to do
};

out& out::operator =(const out& other)
{
    if (this != &other) {
        __print = other.__print;
        __base = other.__base;
        __precision = other.__precision;
    }
    return *this;
};

out::~out()
{
    // nothing to do
};

} /* namespace io */

测试iocout.ino

#include <Arduino.h>
#include "src/cout.h"

/******************************************************************************/
/*** PINS & GLOBALS                                                         ***/
/******************************************************************************/

const uint32_t SERIAL_BAUDRATE = 4800;

/******************************************************************************/
/*** RESOURCES                                                              ***/
/******************************************************************************/

/******************************************************************************/
/*** MAIN                                                                   ***/
/******************************************************************************/

/**
 * setup:
 * sets up the resources used within the arduino
 */
void setup()
{
    /* Initialize serial */
    Serial.begin(SERIAL_BAUDRATE);
    while (!Serial)
    {
        /* Needed by Arduino Leonardo */
    }

    /* new c++-like access to serial! */
    io::cout << "##### Arduino Station #####\n\n"
            << "- io::cout test 1.0" << io::endl;
}

/**
 * loop:
 *
 */
void loop()
{
    /* compute deltaTime */
    uint32_t curr_time = millis();
    static uint32_t start_time = curr_time; // note: initialized once!
    uint32_t deltaTime = curr_time - start_time;
    start_time = curr_time;

    io::cout << "\n> Last loop duration was: ";

    io::cout << io::setprecision(3)
            << deltaTime/1000.0f
            << " s." << io::endl;

    io::cout << "> 1025 in binary is: "
            << io::setbase(BIN)
            << 1025 << io::endl;

    delay(10000);
}

Arduino字符串连接Serial.println（）不起作用

1 个答案: