basic_string::compare
Performs a case sensitive comparison with a specified string to determine if the two strings are equal or if one is lexicographically less than the other.
int compare(
const basic_string<CharType, Traits, Allocator>& _Str
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const basic_string<CharType, Traits, Allocator>& _Str
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const basic_string<CharType, Traits, Allocator>& _Str,
size_type _Off,
size_type _Count
) const;
int compare(
const value_type* _Ptr
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const value_type* _Ptr
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const value_type* _Ptr
size_type _Num2
) const;
Parameters
_Str
The string that is to be compared to the operand string._Pos1
The index of the operand string at which the comparison begins._Num1
The maximum number of characters from the operand string to be compared._Num2
The maximum number of characters from the parameter string to be compared._Off
The index of the parameter string at which the comparison begins._Count
The maximum number of characters from the parameter string to be compared._Ptr
The C-string to be compared to the operand string.
Return Value
A negative value if the operand string is less than the parameter string; zero if the two strings are equal; or a positive value if the operand string is greater than the parameter string.
Remarks
The compare member functions compare either all or part of the parameter and operand strings depending on which in used.
The comparison performed is case sensitive.
Example
// basic_string_compare.cpp
// compile with: /EHsc
#include <string>
#include <iostream>
int main( )
{
using namespace std;
// The first member function compares
// an operand string to a parameter string
int comp1;
string s1o ( "CAB" );
string s1p ( "CAB" );
cout << "The operand string is: " << s1o << endl;
cout << "The parameter string is: " << s1p << endl;
comp1 = s1o.compare ( s1p );
if ( comp1 < 0 )
cout << "The operand string is less than "
<< "the parameter string." << endl;
else if ( comp1 == 0 )
cout << "The operand string is equal to "
<< "the parameter string." << endl;
else
cout << "The operand string is greater than "
<< "the parameter string." << endl;
cout << endl;
// The second member function compares part of
// an operand string to a parameter string
int comp2a, comp2b;
string s2o ( "AACAB" );
string s2p ( "CAB" );
cout << "The operand string is: " << s2o << endl;
cout << "The parameter string is: " << s2p << endl;
comp2a = s2o.compare ( 2 , 3 , s2p );
if ( comp2a < 0 )
cout << "The last three characters of "
<< "the operand string\n are less than "
<< "the parameter string." << endl;
else if ( comp2a == 0 )
cout << "The last three characters of "
<< "the operand string\n are equal to "
<< "the parameter string." << endl;
else
cout << "The last three characters of "
<< "the operand string\n is greater than "
<< "the parameter string." << endl;
comp2b = s2o.compare ( 0 , 3 , s2p );
if ( comp2b < 0 )
cout << "The first three characters of "
<< "the operand string\n are less than "
<< "the parameter string." << endl;
else if ( comp2b == 0 )
cout << "The first three characters of "
<< "the operand string\n are equal to "
<< "the parameter string." << endl;
else
cout << "The first three characters of "
<< "the operand string\n is greater than "
<< "the parameter string." << endl;
cout << endl;
// The third member function compares part of
// an operand string to part of a parameter string
int comp3a;
string s3o ( "AACAB" );
string s3p ( "DCABD" );
cout << "The operand string is: " << s3o << endl;
cout << "The parameter string is: " << s3p << endl;
comp3a = s3o.compare ( 2 , 3 , s3p , 1 , 3 );
if ( comp3a < 0 )
cout << "The three characters from position 2 of "
<< "the operand string are less than\n "
<< "the 3 characters parameter string "
<< "from position 1." << endl;
else if ( comp3a == 0 )
cout << "The three characters from position 2 of "
<< "the operand string are equal to\n "
<< "the 3 characters parameter string "
<< "from position 1." << endl;
else
cout << "The three characters from position 2 of "
<< "the operand string is greater than\n "
<< "the 3 characters parameter string "
<< "from position 1." << endl;
cout << endl;
// The fourth member function compares
// an operand string to a parameter C-string
int comp4a;
string s4o ( "ABC" );
const char* cs4p = "DEF";
cout << "The operand string is: " << s4o << endl;
cout << "The parameter C-string is: " << cs4p << endl;
comp4a = s4o.compare ( cs4p );
if ( comp4a < 0 )
cout << "The operand string is less than "
<< "the parameter C-string." << endl;
else if ( comp4a == 0 )
cout << "The operand string is equal to "
<< "the parameter C-string." << endl;
else
cout << "The operand string is greater than "
<< "the parameter C-string." << endl;
cout << endl;
// The fifth member function compares part of
// an operand string to a parameter C-string
int comp5a;
string s5o ( "AACAB" );
const char* cs5p = "CAB";
cout << "The operand string is: " << s5o << endl;
cout << "The parameter string is: " << cs5p << endl;
comp5a = s5o.compare ( 2 , 3 , s2p );
if ( comp5a < 0 )
cout << "The last three characters of "
<< "the operand string\n are less than "
<< "the parameter C-string." << endl;
else if ( comp5a == 0 )
cout << "The last three characters of "
<< "the operand string\n are equal to "
<< "the parameter C-string." << endl;
else
cout << "The last three characters of "
<< "the operand string\n is greater than "
<< "the parameter C-string." << endl;
cout << endl;
// The sixth member function compares part of
// an operand string to part of an equal length of
// a parameter C-string
int comp6a;
string s6o ( "AACAB" );
const char* cs6p = "ACAB";
cout << "The operand string is: " << s6o << endl;
cout << "The parameter C-string is: " << cs6p << endl;
comp6a = s6o.compare ( 1 , 3 , cs6p , 3 );
if ( comp6a < 0 )
cout << "The 3 characters from position 1 of "
<< "the operand string are less than\n "
<< "the first 3 characters of the parameter C-string."
<< endl;
else if ( comp6a == 0 )
cout << "The 3 characters from position 2 of "
<< "the operand string are equal to\n "
<< "the first 3 characters of the parameter C-string."
<< endl;
else
cout << "The 3 characters from position 2 of "
<< "the operand string is greater than\n "
<< "the first 3 characters of the parameter C-string."
<< endl;
cout << endl;
}
The operand string is: CAB The parameter string is: CAB The operand string is equal to the parameter string. The operand string is: AACAB The parameter string is: CAB The last three characters of the operand string are equal to the parameter string. The first three characters of the operand string are less than the parameter string. The operand string is: AACAB The parameter string is: DCABD The three characters from position 2 of the operand string are equal to the 3 characters parameter string from position 1. The operand string is: ABC The parameter C-string is: DEF The operand string is less than the parameter C-string. The operand string is: AACAB The parameter string is: CAB The last three characters of the operand string are equal to the parameter C-string. The operand string is: AACAB The parameter C-string is: ACAB The 3 characters from position 2 of the operand string are equal to the first 3 characters of the parameter C-string.
Requirements
Header: <string>
Namespace: std