Comparison and testing of strings and characters (source code from Microsoft Help)

// basic_string_compare.cpp

// compile with: /EHsc#include 

#include int main( ) { 

using namespace std; 

// The first member function compares 

// an operand string to a parameter string int comp1; 

string s1o ( "CAB" ); s

tring 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;}

Running result:

The operand string is: CABThe parameter string is: CABThe operand string is equal to the parameter string.The operand string is: AACABThe parameter string is: CABThe 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: AACABThe parameter string is: DCABDThe three characters from position 2 of the operand string are equal to the 3 characters parameter string from position 1.The operand string is: ABCThe parameter C-string is: DEFThe operand string is less than the parameter C-string.The operand string is: AACABThe parameter string is: CABThe last three characters of the operand string are equal to the parameter C-string.The operand string is: AACABThe parameter C-string is: ACABThe 3 characters from position 2 of the operand string are equal to the first 3 characters of the parameter C-string.

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