杂项

常用拼接：

char* + int

转换为char*

char* str = "hello";
int a = 10;
char *buffer = new char[strlen(str)+sizeof(a)+1];
sprintf(buffer, "_%s_%d_", str, a);
cout << buffer << endl;

转换为string

string s = "hello";
int a = 10;
s += to_string(a);
cout << s << endl;

转换为string(利用字符串io流)

string s = "hello";

int a = 10;
ostringstream ss;
ss << s << a << endl;
s = ss.str();
cout << s << endl;

常用拆分:

voidTestStrtok()

{

    //1.非线程安全的,如果多个线程同时调用,会覆盖掉原来的值.

    //2.支持以字符串分割.

    //3.源字符串必须是可修改的.

    charc_str[]="google||twitter||facebook||microsoft||apple||ibm||";

    constchar* delim = "||";

    char* result = strtok(c_str,delim);

    while(result != NULL)

    {

        cout << result << endl;

        result = strtok(NULL,delim);

    }

}

voidTestGetLineWithStringStream()

{

    //1.线程安全的,但是只能以字符作为分隔符

    stringstream ss("google|twitter|facebook|microsoft|apple|ibm|");

    string str;

    while(getline(ss,str,'|'))

    {

        cout << str << endl;

    }

}

 

voidTestStringFind()

{

    //1.自己实现,线程安全,支持字符串作为分隔符.缺点可能就是代码量多.

    string str = "google||twitter||facebook||microsoft||apple||ibm||";

    constchar* delim = "||";

    constint len = strlen(delim);

    size_t index = 0;

    size_t pos = str.find(delim,index);

    while(pos != string::npos)

    {

        string ss = str.substr(index,pos-index);

        cout << ss << endl;

        index = pos+len;

        pos = str.find(delim,index);

    }

 

    //cout << "is last?" << " index:" << index << " str.length():" << str.length() << endl;

    if((index+1) < str.length())

    {

        string ss = str.substr(index,str.length() - index);

        cout << ss << endl;

    }

}