c++ - Boost Property Tree Json Read for file containing LPWSTR -

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i have code supposed write content in file using writefile. type of contents written in file lpwstr ie wchar_t *. file write ip, ssl , compression. consider following code:

#include <windows.h> #include <iostream> #include <boost/property_tree/ptree.hpp> #include <boost/property_tree/json_parser.hpp> int main() {     lpwstr ip = null;     lpwstr ssl = null;     lpwstr comp = null;     wchar_t buffer[300];     handle hfile;     bool berrorflag;     dword dwbytestowrite = 0; //(dword)strlen(buffer);     dword dwbyteswritten = 0;      if(ip == null  || wcslen(ip) == 0 )     {         ip = l"127.0.0.1";     }      if(ssl == null || wcslen(ssl) == 0)     {         ssl = l"false";     }      if(comp == null || wcslen(comp) == 0 )     {         comp = l"true";     }       wsprintf(buffer, l"{\n\"ip\": \"%ls\",\n\"ssl\": \"%ls\",\n\"compression\":\"%ls\"\n}",ip,ssl,comp);     //swprintf(buffer, 150, l"{\n\"ipaddress\": \"%ls\",\n\"ssl\": \"%ls\",\n\"compression\":\"%ls\"\n}",ip,ssl,comp);     std::wcout << buffer << std::endl;     dwbytestowrite = (wcslen(buffer)) * sizeof(wchar_t);      hfile = createfile(l"c://somefolder//some_config.config",                // name of write                        generic_write,          // open writing                        0,                      // not share                        null,                   // default security                        create_always,             // create new file                        file_attribute_normal,  // normal file                        null);       berrorflag = writefile(                      hfile,           // open file handle                     buffer,      // start of data write                     dwbytestowrite,  // number of bytes write                     &dwbyteswritten, // number of bytes written                     null);            // no overlapped structure        closehandle(hfile);       boost::property_tree::ptree pt;       try       {           boost::property_tree::read_json("c://somefolder//some_config.config", pt);       }       catch(std::exception &e)       {           std::cout << e.what();       }       try       {           std::cout << pt.get<std::string>("ip");       }       catch(std::exception &e)       {           std::cout << e.what();       } }

the contents of file have

{ "ip": "127.0.0.1", "ssl": "false", "compression":"true" }

but using read_json fails , gives error:

c://somefolder//some_config.config(1): expected object name  no such node (ip)

what wrong in code? why can't read_json reads file written? if using writefile incorrectly, please correct me. thanks.

you want use wptree:

boost::property_tree::wptree pt; boost::property_tree::read_json("c://somefolder//some_config.config", pt); std::wcout << pt.get<std::wstring>(l"ip");

note l"ip" , wstring there.

sidenote: need const versions of lpwstr pointers (lpcwstr? guess) if you're assigning string literals


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