In PHP programming, we often encounter some functions that produce output directly, such as PassThru (), ReadFile (), Var_dump (), and so on. But sometimes we want to import the output of these functions into a file, or we can process and output them first Or, the output of these functions is treated as a string.
Then we're going to use the output buffer function.
There are a number of functions that process output buffering:
Ob_start () starts the output buffer, when PHP stops the output, after which the output is transferred to an internal buffer.
Ob_get_contents () This function returns the contents of the internal buffer. This is tantamount to turning these outputs into strings.
Ob_get_ Length () returns the size of the internal buffer.
Ob_end_flush () ends the output buffer and outputs the contents of the buffer. The output after this is the normal output.
Ob_end_clean () ends the output buffer and discards the contents of the buffer.
For example, the Var_dump () function outputs the structure and content of a variable, which is useful when debugging.
But if the contents of the variable have <, > and other HTML special characters, output to the Web page can not be seen. What do we do?
The output buffering function can be used to solve this problem easily.
Ob_start ();
Var_dump ($var);
$out = Ob_get_contents ();
Ob_end_clean ();
At this point the output of var_dump () already exists $out. You can output it now:
Echo ' <pre> '. Htmlspecialchars ($out). ' </pre> ';
Or wait until the future, or send this string to the template (Template) and then output.
