Php/docs/function.odbc-binmode

• PHP Manual
• ODBC 函数
• Handling of binary column data

odbc_binmode

(PHP 4, PHP 5, PHP 7)

odbc_binmode — Handling of binary column data

说明

odbc_binmode ( resource $result_id , 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:

LONGVARBINARY handling

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).

参数

result_id

The result identifier.

If result_id is 0, 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

Note:

Handling of binary long columns is also affected by odbc_longreadlen().

返回值

成功时返回 true， 或者在失败时返回 false。