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c++算法使用json输出最终结果给java使用，于是，开始了json对象的组装之旅...

首先，对不同数据类型，封装不同的数据组装函数

/** * 拼接int */std::string getKeyValue(std::string sKey, int iValue){    char szDoubleQutoes[] = "\"";    char szColon[] = ":";    char szValue[50] = { 0 };    std::string strResult;    strResult.append(szDoubleQutoes);    strResult.append(sKey);    strResult.append(szDoubleQutoes);    strResult.append(szColon);    sprintf(szValue, "%d", iValue);    strResult.append(szValue);    return strResult;}/** * 拼接float，保留3位 */std::string getKeyValue(std::string sKey, float fValue){    char szDoubleQutoes[] = "\"";    char szColon[] = ":";    char szValue[50] = { 0 };    std::string strResult;    strResult.append(szDoubleQutoes);    strResult.append(sKey);    strResult.append(szDoubleQutoes);    strResult.append(szColon);    sprintf(szValue, "%0.3f", fValue);    strResult.append(szValue);    return strResult;}/** * 拼接string */std::string getKeyValue(std::string sKey, std::string sValue){    char szDoubleQutoes[] = "\"";    char szColon[] = ":";    std::string strResult;    strResult.append(szDoubleQutoes);    strResult.append(sKey);    strResult.append(szDoubleQutoes);    strResult.append(szColon);    strResult.append(szDoubleQutoes);    strResult.append(sValue);    strResult.append(szDoubleQutoes);    return strResult;}/** * 拼接object */std::string getKeyValueObject(std::string sKey, std::string sObject){    char szDoubleQutoes[] = "\"";    char szColon[] = ":";    std::string strResult;    strResult.append(szDoubleQutoes);    strResult.append(sKey);    strResult.append(szDoubleQutoes);    strResult.append(szColon);    strResult.append(sObject);    return strResult;}/** * 拼接array */std::string getKeyValueArray(std::string sKey, std::string sArray){    char szDoubleQutoes[] = "\"";    char szColon[] = ":";    std::string strResult;    strResult.append(szDoubleQutoes);    strResult.append(sKey);    strResult.append(szDoubleQutoes);    strResult.append(szColon);    strResult.append("[");    strResult.append(sArray);    strResult.append("]");    return strResult;}

调用，及最终json组装，增加 { }及，分隔符

int main() {    int value1 = 1;    float value2 = 1.0f;    std::string strJsonResult("{");    strJsonResult.append(getKeyValue("key1", value1));     strJsonResult.append(",");    strJsonResult.append(getKeyValue("key2", value2));    strJsonResult.append("}");}

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