This paper introduces the function of string interception from PHP's own interception function to the final support of Chinese, English and English mixed string interception methods, a friend of the need to refer to.
Takes a partial string.
Syntax: String substr (string string, int start, int [length]);
return value: String
Function type: Data processing
Content Description
This function takes the string starting at the start of the string to take a length character. If start is negative, it is counted from the end of the string. If the omitted parameter length exists, but is a negative number, it is taken to the penultimate length character.
Usage examples
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echo substr ("abcdef", 1, 3); Returns "BCD"
echo substr ("ABCdef",-2); Back to "EF"
echo substr ("ABCdef",-3, 1); Return "D"
echo substr ("abcdef", 1,-1); Back to "BCDE"
?> |
The above only supports English does not support Chinese
Intercept GB2312 Chinese string
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< PHP
Intercept Chinese strings
function Mysubstr ($str, $start, $len) {
$tmpstr = "";
$strlen = $start + $len;
for ($i = 0; $i < $strlen; $i + +) {
if (Ord (substr ($str, $i, 1)) > 0xa0) {
$tmpstr. = substr ($str, $i, 2);
$i + +;
} else
$tmpstr. = substr ($str, $i, 1);
}
return $tmpstr;
}
?> |
Intercepting UTF8 encoded multibyte strings
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< PHP
Intercept UTF8 string
function Utf8substr ($str, $from, $len)
{
Return Preg_replace (' #^ (?: [x00-x7f]|[ xc0-xff][x80-xbf]+) {0, '. $from. '} '.
' (?: [x00-x7f]| [Xc0-xff] [x80-xbf]+) {0, '. $len. '}). * #s ',
' $ ', $str);
}
?> |
/*
* Function: function as substr, except it will not cause garbled
Parameters
Returns
*/
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function Utf8_substr ($str, $start, $length =null) {
The normal interception of the first time.
$res = substr ($str, $start, $length);
$strlen = strlen ($STR);
/* Go ahead and determine whether the 6 bytes are complete (not mutilated). */ If the argument start is a positive number
if ($start >= 0) {
Go ahead and intercept about 6 bytes.
$next _start = $start + $length; Initial position
$next _len = $next _start + 6 <= $strlen? 6: $strlen-$next _start;
$next _segm = substr ($str, $next _start, $next _len); If the 1th byte is not the first byte of the full character, then intercept about 6 bytes
$prev _start = $start-6 > 0? $start-6:0;
$prev _segm = substr ($str, $prev _start, $start-$prev _start);
}
Start is a negative number
else{
Go ahead and intercept about 6 bytes.
$next _start = $strlen + $start + $length; Initial position
$next _len = $next _start + 6 <= $strlen? 6: $strlen-$next _start;
$next _segm = substr ($str, $next _start, $next _len);
If the 1th byte is not the first byte of the full character, then the next intercept is about 6 bytes.
$start = $strlen + $start;
$prev _start = $start-6 > 0? $start-6:0;
$prev _segm = substr ($str, $prev _start, $start-$prev _start);
} Determine if the first 6 bytes conform to the UTF8 rule
if (Preg_match (' @^ ([x80-xbf]{0,5}) [xc0-xfd]?@ ', $next _segm, $bytes)) {
if (!empty ($bytes [1])) {
$bytes = $bytes [1];
$res. = $bytes;
}
} Determine if 6 bytes are compliant with the UTF8 rule
$ord 0 = ord ($res [0]);
if (<= $ord 0 && 191 >= $ord 0) {
Intercept it and add it to the front of Res.
if (Preg_match (' @[xc0-xfd][x80-xbf]{0,5}$@ ', $prev _segm, $bytes)) {
if (!empty ($bytes [0])) {
$bytes = $bytes [0];
$res = $bytes. $res;
}
}
} return $res;
} |
Test data::
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$str = ' dfjdjf 13f test 65&2 Data FD J (1 on Mfe& Just ';
Var_dump (Utf8_substr ($STR, +)); Echo '
';
Var_dump (Utf8_substr ($STR, 6)); Echo '
';
Var_dump (Utf8_substr ($STR, 9,)); Echo '
';
Var_dump (Utf8_substr ($STR, +)); Echo '
' ;
Var_dump (Utf8_substr ($STR, 6)); Echo '
'; |
Display Result::(interception without garbled, welcome to test, submit bug)
String (12) "according to FDJ"
String (26) "According to FDJ (1 on Mfe& ...")
String ("13f test 65&2 number")
String (12) "Data FD"
String "DJ (1 Mfe& ...")
To share what I used to do.
Now let's look at the Chinese truncation function.
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function Moocutstr ($string, $length, $dot = ' ... ') {
Global $charset; if (strlen ($string) <= $length) {
return $string;
}
$string = Str_replace (' & ', ' ' ', ' < ', ' > '), Array (' & ', ' "', ' < ', ' > '), $string);
$strcut = ";
if (Strtolower ($charset) = = ' Utf-8 ') {
$n = $tn = $noc = 0;
while ($n < strlen ($string)) {
$t = Ord ($string [$n]);
if ($t = = 9 | | $t = = 10 | | (<= $t && $t <= 126)) {
$tn = 1; $n + +; $noc + +;
} elseif (194 <= $t && $t <= 223) {
$tn = 2; $n + = 2; $noc + = 2;
} elseif (224 <= $t && $t < 239) {
$tn = 3; $n + = 3; $noc + = 2;
} elseif (<= $t && $t <= 247) {
$tn = 4; $n + = 4; $noc + = 2;
} elseif (248 <= $t && $t <= 251) {
$tn = 5; $n + = 5; $noc + = 2;
} elseif ($t = = 252 | | $t = = 253) {
$tn = 6; $n + = 6; $noc + = 2;
} else {
$n + +;
}
if ($noc >= $length) {
Break
}
}
if ($noc > $length) {
$n-= $tn;
}
$strcut = substr ($string, 0, $n);
} else {
for ($i = 0; $i < $length; $i + +) {
$strcut. = Ord ($string [$i]) > 127? $string [$i]. $string [+ + $i]: $string [$i];
}
}
$strcut = Str_replace (' & ', ' ' ', ' < ', ' > '), Array (' & ', ' "', ' < ', ' > '), $strcut); return $strcut. $dot;
} |
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