How do I put an array of unsigned char* pointers into json

[dingyaoyang]

If I have a array like this, I can do it well

unsigned char arr[128];
json jres;
jres["data"] = arr;

But what to do if this is the case：

int len = 10;
unsigned char arr[len]; // or unsigned char* arr = (unsigned char*)malloc(sizeof(unsigned char)*len);

I can't directly assign it to json. I also can't convert it to a string first, because maybe arr[len] = {'\201','\234',...};.

[dingyaoyang]

use vector<unsigned char>