Monday 25 May 2015
The DifferenceBetween the echo and print Commands
Generally you have seen the echo command used in a number of different ways to output text from the server to your browser. In some cases, a string literal has been output.
In others, strings have first been concatenated or variables have been evaluated.
But there is also an alternative to echo that you can use: print. The two commands are quite similar, but print is a function-like construct that takes a single parameter and has a return value (which is always 1), where as echo is purely a PHP language construct.
Since both commands are constructs, neither requires parentheses.
Since both commands are constructs, neither requires parentheses.
By and large, the echo command will be a tad faster than print in general text output, because it doesn’t set a return value. On the other hand, because it isn’t implemented like a function, echo cannot be used as part of a more complex expression, whereas print can. Here’s an example to output whether the value of a variable is TRUE or FALSE using print, something you could not perform in the same manner with echo, because it would display a Parse error message:
$b ? print "TRUE" : print "FALSE";
The question mark is simply a way of interrogating whether variable $b is TRUE or FALSE. Whichever command is on the left of the following colon is executed if $b is TRUE, whereas the command to the right is executed if $bis FALSE.
I generally, use echo, and I recommend that you do so as well until you reach such a point in your PHP development that you discover the need for using print.
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