iconv_substr
(PHP 5)
iconv_substr — Cut out part of a string
说明
string iconv_substr
( string $str
, int $offset
[, int $length
[, string $charset
]] )
Cuts a portion of str
specified by the
offset
and length
parameters.
参数
-
str
-
The original string.
-
offset
-
If offset
is non-negative,
iconv_substr() cuts the portion out of
str
beginning at offset
'th
character, counting from zero.
If offset
is negative,
iconv_substr() cuts out the portion beginning
at the position, offset
characters
away from the end of str
.
-
length
-
If length
is given and is positive, the return
value will contain at most length
characters
of the portion that begins at offset
(depending on the length of string
).
If negative length
is passed,
iconv_substr() cuts the portion out of
str
from the offset
'th
character up to the character that is
length
characters away from the end of the string.
In case offset
is also negative, the start position
is calculated beforehand according to the rule explained above.
-
charset
-
If charset
parameter is omitted,
string
are assumed to be encoded in
iconv.internal_encoding.
Note that offset
and length
parameters are always deemed to represent offsets that are
calculated on the basis of the character set determined by
charset
, whilst the counterpart
substr() always takes these for byte offsets.
返回值
Returns the portion of str
specified by the
offset
and length
parameters.
If str
is shorter than offset
characters long, FALSE will be returned.