C++ string 分割 split 与合并 join

封装类似java和js的split和join函数

vector<string> split(char c, string src){
    vector<string> res;
    int sp = 0,fp=0;
    while(fp<src.length()){
        fp = src.find(c,sp);
        res.push_back(src.substr(sp,fp-sp));
        sp = fp + 1;
    }
    return res;
}

string join(char c, vector<string> src){
    string res = "";
    if(src.size() == 0) return res;

    vector<string>::iterator it = src.begin();
    res += *it;
    
    for(it++;it!=src.end();it++){
        res += c;
        res += *it;
    }
    return res;
}

// 按长度分割字符串，长度不足按指定字符补齐
vector<string> splitByLength(int len, char c, string src){
    vector<string> res;
    while(src.length()>=8){
        res.push_back(src.substr(0,len));
        src.erase(0,len);
    }
    if(src.length()>0){
        int k = 8 - src.length();
        res.push_back(src+string(k,c));
    }
    return res;
}