stdstring

I'm using std::string and need to left pad them to a given width. What is the recommended way to do this in C++? Sample input: 123 pad to 10 characters. Sample output: 123 (7 spaces in front of 123) std::setw (setwidth) manipulator std::cout << std::setw (10) << 77 << std::endl; or std::cout << std::setw (10) << "hi!" << std::endl; outputs padded 77 and "hi!". if you need result as string use instance of std::stringstream instead std::cout object. ps: responsible header file <iomanip> void padTo(std::string &str, const size_t num, const char paddingChar = ' ') { if(num > str.size()) str.insert

I am working with an open-source UNIX tool that is implemented in C++, and I need to change some code to get it to do what I want. I would like to make the smallest possible change in hopes of getting my patch accepted upstream. Solutions that are implementable in standard C++ and do not create more external dependencies are preferred. Here is my problem. I have a C++ class -- let's call it "A" -- that currently uses fprintf() to print its heavily formatted data structures to a file pointer. In its print function, it also recursively calls the identically defined print functions of several

I need to compare strings to decide whether they represent the same thing. This relates to case titles entered by humans where abbreviations and other small details may differ. For example, consider the following two titles: std::string first = "Henry C. Harper v. The Law Offices of Huey & Luey, LLP"; As opposed to: std::string second = "Harper v. The Law Offices of Huey & Luey, LLP"; A human can quickly gauge that these are most likely one and the same. The current approach I have taken is to normalize the strings by lowercasing all letters and removing all punctuation and spaces giving: std:

Is there anyway to read a known number of bytes, directly into an std::string, without creating a temporary buffer to do so? eg currently I can do it by boost::uint16_t len; is.read((char*)&len, 2); char *tmpStr = new char[len]; is.read(tmpStr, len); std::string str(tmpStr, len); delete[] tmpStr; std::string has a resize function you could use, or a constructor that'll do the same: boost::uint16_t len; is.read((char*)&len, 2); std::string str(len, '\0'); is.read(&str[0], len); This is untested, and I don't know if strings are mandated to have contiguous storage. You could use a combination of

In C++11, we know that std::string is guaranteed to be both contiguous and null-terminated (or more pedantically, terminated by charT() , which in the case of char is the null character 0). There is this C API I need to use that fills in a string by pointer. It writes the whole string + null terminator. In C++03, I was always forced to use a vector<char> , because I couldn't assume that string was contiguous or null-terminated. But in C++11 (assuming a properly conforming basic_string class, which is still iffy in some standard libraries), I can. Or can I? When I do this: std::string str

I know it is a common issue, but looking for references and other material I don't find a clear answer to this question. Consider the following code: #include <string> // ... // in a method std::string a = "Hello "; std::string b = "World"; std::string c = a + b; The compiler tells me it cannot find an overloaded operator for char[dim] . Does it mean that in the string there is not a + operator? But in several examples there is a situation like this one. If this is not the correct way to concat more strings, what is the best way? Your code, as written, works. You’re probably trying to achieve

Problem: I have an integer; this integer needs to be converted to a stl::string type. In the past, I've used stringstream to do a conversion, and that's just kind of cumbersome. I know the C way is to do a sprintf , but I'd much rather do a C++ method that is typesafe(er). Is there a better way to do this? Here is the stringstream approach I have used in the past: std::string intToString(int i) { std::stringstream ss; std::string s; ss << i; s = ss.str(); return s; } Of course, this could be rewritten as so: template<class T> std::string t_to_string(T i) { std::stringstream ss; std::string s;

I need to use an std::string to store data retrieved by fgets() . To do this I need to convert the char* return value from fgets() into an std::string to store in an array. How can this be done? std::string has a constructor for this: const char *s = "Hello, World!"; std::string str(s); Just make sure that your char * isn't NULL , or else the behavior is undefined. If you already know size of the char*, use this instead char* data = ...; int size = ...; std::string myString(data, size); This doesn't use strlen. EDIT: If string variable already exists, use assign(): std::string myString; char*