PHP - Output Buffer
Table of Contents
About
An output buffer is a mechanism to capture all input of output function
Note that once the buffer is above its max limit set by output-buffering (get its actual size with ob_get_length), there is automatic flush.
Basic
- You create a capture session of the buffer with ob_start
ob_start();
- The php script generates output
echo "My output"
print "Whatever"
- You get the content with with ob_get_contents
ob_get_contents();
- You clean and end the actual capture session with ob_end_clean
ob_end_clean();
Nested / Level
This is a nested feature meaning that a sub-function may also create and end a capture session (ob_start, ob_end) to capture the output of its own instructions
ie:
- A root function can start to capture the output with ob_start (making the level of ob_get_level to 1)
- A sub-function of function can also start to capture the output with ob_start (making the level of ob_get_level to 2)
- The sub-function can get and the capture with ob_end (making the level of ob_get_level back to 1)
- The root function can get and the capture with ob_end (making the level of ob_get_level back to 0)
Support
phpunit: Test code or tested code did not (only) close its own output buffers
See the dedicated page: How to solve Test code or tested code did not (only) close its own output buffers
