页面何时发送到客户端浏览器？

Question

When i build a set of elements (say 100) with php (in a loop) Is the page send to the client only when the loop is completed or is the page on client side already showing on the client before the loop is completed? Thanks

Answer 1

You can control output to client browser anytime in your PHP code

Example Send to Client Instantly

for($i = 0; $i < 100; $i ++) {
    echo $i, " - sent ";
    sleep(1);
    flush(); // Send to client Instantly 
}

Example Send after Loop

ob_start();
for($i = 0; $i < 100; $i ++) {
    echo $i, " - sent ";
    sleep(1);
}
ob_end_flush() // Send after loop

Example 3 ( This would just use your default output buffer configuration )

for($i = 0; $i < 100; $i ++) {
    echo $i, " - sent ";
    sleep(1);
}

Finally (Credit : Ninsuo)

Some browsers does not display anything until the page is fully loaded so we don't always control flushing