odbc_binmode
(PHP 4, PHP 5, PHP 7, PHP 8)
odbc_binmode — Handling of binary column data
說明
$statement
, int $mode
): bool
Controls handling of binary column data. ODBC SQL types affected are
BINARY
, VARBINARY
, and
LONGVARBINARY
.
The default mode can be set using the
uodbc.defaultbinmode php.ini directive.
When binary SQL data is converted to character C data (ODBC_BINMODE_CONVERT
), each byte
(8 bits) of source data is represented as two ASCII characters.
These characters are the ASCII character representation of the
number in its hexadecimal form. For example, a binary
00000001
is converted to
"01"
and a binary 11111111
is converted to "FF"
.
While the handling of BINARY
and VARBINARY
columns only depend on the binmode, the handling of LONGVARBINARY
columns also depends on the longreadlen as well:
binmode | longreadlen | result |
---|---|---|
ODBC_BINMODE_PASSTHRU |
0 | passthru |
ODBC_BINMODE_RETURN |
0 | passthru |
ODBC_BINMODE_CONVERT |
0 | passthru |
ODBC_BINMODE_PASSTHRU |
>0 | passthru |
ODBC_BINMODE_RETURN |
>0 | return as is |
ODBC_BINMODE_CONVERT |
>0 | return as char |
If odbc_fetch_into() is used, passthru means that an empty string is returned for these columns. If odbc_result() is used, passthru means that the data are sent directly to the client (i.e. printed).
參數
-
statement
-
The result identifier.
If
statement
is0
, the settings apply as default for new results. -
mode
-
Possible values for
mode
are:-
ODBC_BINMODE_PASSTHRU
: Passthru BINARY data -
ODBC_BINMODE_RETURN
: Return as is -
ODBC_BINMODE_CONVERT
: Convert to char and return
注意: Handling of binary long columns is also affected by odbc_longreadlen().
-
返回值
成功時返回 true
, 或者在失敗時返回 false
。