Found in the string in the processing of this string is very useful, just found an article put here. Use string instead of char * array, sort using sort sort algorithm, and use the unique function to go heavy
1, Define
string S1 = "Hello";
String s2 = "World";
String s3 = S1 + "," + s2 + "!\n";
2, append
S1 + = ", shanshan\n";
3, Compare
if (S1 = = s2)
.....
else if (S1 = = "Hello")
.....
4, string overloaded many operators, including +, + =, <,, =, , [], <<, >>, etc., formal these operators, the string operation is very convenient #include<string>
#include<iostream>
using namespaceStd
intMain () {
String Strinfo= "Please input your name:";
cout << Strinfo;
Cin >> Strinfo;
if(Strinfo = = "Winter" )
cout << "You are winter!"<<endl;
Else if(Strinfo! = "Wende" )
cout << "You is not wende!"<<endl;
Else if(Strinfo < "Winter")
cout << "your name should be ahead of winter"<<endl;
Else
cout << "your name should is after of winter"<<endl;
Strinfo + = ", Welcome to china!";
cout << strinfo<<endl;
cout << "Your name is:"<<endl;
String strtmp = "How is it ?"+ Strinfo;
for(inti = 0; I < strtmp.size (); i + +)
cout<<strtmp[i];
return0;
} 5. Find function
Because lookups are one of the most frequently used features, String provides a very rich look-up function. The list is as follows:
| function name |
description |
| find |
find |
| rfind |
reverse lookup |
| find_fi rst_of |
|
| find_first_not_of |
find any character that does not contain a substring, return to the first position |
| find_last_of |
find any characters that contain substrings, return to the last position |
| find_last_not_of |
find any characters that do not contain substrings, return to the last position |
The above functions are overloaded 4 times, the following is the FIND_FIRST_OF function as an example of their arguments, the other functions and their parameters, that is, a total of 24 functions:
Size_type find_first_of (Constbasic_string& s, size_type pos = 0)
Size_type find_first_of (Constchart* s, size_type pos, Size_type N)
Size_type find_first_of (Constchart* s, size_type pos = 0)
Size_type find_first_of (CharT c, size_type pos = 0)
All lookup functions return a size_type type, which is typically the location of the string found and returns String::npos if not found.
In fact, String::npos represents-1. Return-1 if not found. Examples are as follows:
#include<string>
#include<iostream>
using namespaceStd
intMain () {
String Strinfo= "//*---Hello Word!......------";
String Strset= "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz";
intFirst = strinfo.find_first_of (Strset);
if(first = = String::npos) {
cout<< "Not find any characters"<<endl;
return-1;
}
intLast = strinfo.find_last_of (Strset);
if(last = = String::npos) {
cout<< "Not find any characters"<<endl;
return-1;
}
cout << strinfo.substr (First, Last-first + 1) <<endl;//string.substr is a substring
return0;
}
6. Insert function, replace function and erase function
The string simply provides the Replace function by location and interval, and cannot replace another string in the specified string with one.
Example:
#include<string>
#include<iostream>
using namespaceStd
intMain () {
String Strinfo= "This is Winter, Winter is a programmer. Do you know Winter?";
cout<< "orign string is: \ n"<<strinfo<<endl;
String_replace (Strinfo, "Winter", "Wende");
cout<< "After replace Winter with Wende, the string is: \ n"<<strinfo<<endl;
return0;
}
String.erase (Pos,srclen);//srclen is the length of the deletion
String.Insert (POS,STRDST); POS is positioned, STRDST is the inserted function
voidString_replace (String & Strbig,ConstString & Strsrc,ConstString &strdst) {
String::size_type pos=0;
String::size_type srclen=strsrc.size ();
String::size_type dstlen=strdst.size ();
while((Pos=strbig.find (STRSRC, pos))! = String::npos) {
Strbig.erase (POS, Srclen);
Strbig.insert (POS, STRDST);
pos + = Dstlen;
}
} |
