C++ Json输出为单行

问题:

使用下面的示例代码，可以创建一个json字符串并按如下方式打印，我的要求是打印到一行（也可以打印到下面），没有空格或制表符，我可以使用boost来完成，还是需要显式地从字符串中删除

#include "boost/property_tree/json_parser.hpp"
#include <boost/property_tree/ptree.hpp>
#include <sstream>
#include <iostream>

    int main()
    {
            boost::property_tree::ptree root;
            root.put("sessionId", "123456");
            root.put("applicationName", "Sample_Appliation");
            root.put("applicationId", "null");
            root.put("logMessage", "Sample Message");
            root.put("loggingTime", "2020-03-17T13:26:45.013");
            std::stringstream ss;
            boost::property_tree::write_json(ss, root);
            std::cout << ss.str() << std::endl;
            return 0;
    }

预期：

{"sessionId": "123456","applicationName": "Sample_Appliation","applicationId": "null","logMessage": "Sample Message","loggingTime": "2020-03-17T13:26:45.013"}

---

boost:：property_tree:：write_json

有第三个参数名为

pretty

，默认值为

true

，只需将

false

作为第三个参数传递即可禁用pretty打印。

大警告：boost PropertyTree。然而，幸运的是，Boost最近采用了新技术，它实际上起到了作用：

#include <boost/json.hpp>
#include <iostream>

int main() {
    auto json = boost::json::parse(R"(
        {
            "sessionId": "123456",
            "applicationName": "Sample_Appliation",
            "applicationId": "null",
            "logMessage": "Sample Message",
            "loggingTime": "2020-03-17T13:26:45.013"
        })");

    std::cout << json;
}

---

使用

boost:：property_tree:：write_json（ss，root，false）输出为一行。
#include <boost/json.hpp>
#include <iostream>

int main() {
    auto json = boost::json::parse(R"(
        {
            "sessionId": "123456",
            "applicationName": "Sample_Appliation",
            "applicationId": "null",
            "logMessage": "Sample Message",
            "loggingTime": "2020-03-17T13:26:45.013"
        })");

    std::cout << json;
}

{"sessionId":"123456","applicationName":"Sample_Appliation","applicationId":"null","logMessage":"Sample Message","loggingTime":"2020-03-17T13:26:45.013"}