解析字符串substr

#include <iostream>
#include <string>
int main()
{
    /*Myvector<double> vec;
    vec.push(1.1f);
    system("pause");
    return 0;*/
    std::string user(" uid:600001, name:張三, score: 125, state:未準備");
    std::string str("{act: login,result : true,room: {rid: 62,roomid : 608807,maxbet : 100,rounds : 10,redix: 0,remain : 10,state: 0},\
        user:[{uid:600001, name: 張三, score : 125, state : 未準備},\
    { uid:600002, name : 李四, score : -125, state : 未準備 }]}");
    std::string left;
    int i = 0;
    while (str.find(",") != std::string::npos)
    {
        /*int a = str.find("{");
        if (a > -1)
        {
            str.erase(a,1);
        }*/
        i = str.find(",");
        left = str.substr(0, i);
        str = str.substr(i + 1);
        if (left.find("{")!=std::string::npos)
        {
            left.erase(0,left.find("{")+1);
        }
        if (left.find("{")!=std::string::npos)
        {
            left.erase(0, left.find("{") + 1);
        }       
        if (str.find("}") != std::string::npos)
        {
            left.erase(0,left.find("}")+1);
        }
        std::cout << left << std::endl;
    }
    if (str.find("}") != std::string::npos)
    {
        str.erase(str.find("}"));
    }   
    std::cout << str << std::endl;
    system("pause");
}