Problems with Setcookie statements

The error message appears:

Warning:cannot Modify header Information-headers already sent by

Solution:

Open Php_ini, search for output_bufferfing, remove the preceding semicolon, modify off to on, or set a numeric value. It's OK.

This type of statement is caused by the problem of the Setcookie statement.

The cookie itself has some restrictions on its use, such as:
1. Call Setcookie? Before the label.
2. Do not use echo before calling Setcookie
3. Until?? After being reopened, does the cookie just get out of the program?
4.setcookie function must be sent out to the browser before any
5 .....

Based on the above restrictions, so the line Setcookie () function, often hit the "Undefined index", "Cannot modify header Information-headers already sent by" ... Wait a minute? Cannot modify header information-headers already sent by "this?? The method is to delay the output of the feed to the browser before the cookie is generated, so you can add Ob_start () to the front of the program; This will solve the problem.