Question

How to binary safe comparison of two strings (string and substring) from an offset, up to length characters in PHP

Answer 1

// int substr_compare(string $main_str , string $str , int $offset 
//                    [, int $length [, bool $case_insensitivity = false ]])

// offset - start position for the comparison. If negative - starts from end of string
// Returns < 0 if main_str < str, > 0 if main_str > str, and 0 if they are equal

echo substr_compare("abcdefg", "bcd", 1, 2) . "<br />" ;
echo substr_compare("abcdefg", "bcd", 1, 3) . "<br />" ; 
echo substr_compare("abcdefg", "bcd", 1, 4) . "<br />" ; 




/*
run:
    
0
0
1
    
*/

 

70+ SQL courses for beginners and professionals

Answer 2

// int substr_compare(string $main_str , string $str , int $offset 
//                    [, int $length [, bool $case_insensitivity = false ]])

// offset - start position for the comparison. If negative - starts from end of string
// Returns < 0 if main_str < str, > 0 if main_str > str, and 0 if they are equal

echo substr_compare("abcdefg", "bcd", -1, 2) . "<br />" ;
echo substr_compare("abcdefg", "bcd", -1, 3) . "<br />" ; 
echo substr_compare("abcdefg", "bcd", -1, 5) . "<br />" ; 
echo substr_compare("abcdefg", "bcd", -6, 3) . "<br />" ; 




/*
run:
    
1
1
1
0
    
*/

 

70+ SQL courses for beginners and professionals

Answer 3

// int substr_compare(string $main_str , string $str , int $offset 
//                    [, int $length [, bool $case_insensitivity = false ]])

// offset - start position for the comparison. If negative - starts from end of string
// Returns < 0 if main_str < str, > 0 if main_str > str, and 0 if they are equal

echo substr_compare("abcdefg", "bcd", 0, 3) . "<br />" ;
echo substr_compare("abcdefg", "bcd", 0, 4) . "<br />" ; 
echo substr_compare("abcdefg", "bcd", 0, 5) . "<br />" ; 




/*
run:
    
-1
-1
-1
    
*/

 

70+ SQL courses for beginners and professionals

Answer 4

// int substr_compare(string $main_str , string $str , int $offset 
//                    [, int $length [, bool $case_insensitivity = false ]])
 
// offset - start position for the comparison. If negative - starts from end of string
// Returns < 0 if main_str < str, > 0 if main_str > str, and 0 if they are equal
 
echo substr_compare("abcdefg", "bcd", 1, 3) . "<br />" ; 
echo substr_compare("abcdefg", "BCD", 1, 3) . "<br />" ;
echo substr_compare("abcdefg", "BCD", 1, 3, true) . "<br />" ; 
 
 
 
/*
run:
     
0
1
0
     
*/

 

70+ SQL courses for beginners and professionals