echo function inside function bug - php

Question

I have the following PHP code:
function button1($attr, $text) {
$data = "<button ";
foreach($attr as $names => $specs) {
$data .= $names . "='" . $specs . "' ";
}
$data .= ">" . $text . "</button>\n";
echo $data;
}
function span1($attr, $text) {
$data = "<span ";
foreach($attr as $names => $specs) {
$data .= $names . "='" . $specs . "' ";
}
$data .= ">" . $text . "</span>\n";
echo $data;
}
button1(
array( "type" => "button",
"class" => "navbar-toggle",
"data-toggle" => "collapse",
"data-target" => ".navbar-collapse"
),
span1(
array( "class" => "sr-only" ),
"Toggle navigation"
)
);
From the code above, I want the result to appear like this:
<button type='button' class='navbar-toggle' data-toggle='collapse' data-target='.navbar-collapse' >
<span class='sr-only' >Toggle navigation</span>
</button>
But instead it appears like this:
<span class='sr-only' >Toggle navigation</span>
<button type='button' class='navbar-toggle' data-toggle='collapse' data-target='.navbar-collapse' ></button>
What must I do to get the result I want? Thanks for your help.

Answer 1

Simple, NEVER echo from functions. The problem is, span1() is being evaluate first which results in its echo executing. It also returns nothing to be used as the button1() $text argument. Then the button1() echo is executed, printing its contents to the output stream after the span1() echo.
Change the last line of each function to
return $data;
and execute it via
echo button1(...);

Answer 2

Replace your PHP code with this,
You have to return $data into functions and also echo button1();
<?php
function button1($attr, $text) {
$data = "<button ";
foreach($attr as $names => $specs) {
$data .= $names . "='" . $specs . "' ";
}
$data .= ">" . $text . "</button>\n";
return $data;
}
function span1($attr, $text) {
$data = "<span ";
foreach($attr as $names => $specs) {
$data .= $names . "='" . $specs . "' ";
}
$data .= ">" . $text . "</span>\n";
return $data;
}
echo button1(
array( "type" => "button",
"class" => "navbar-toggle",
"data-toggle" => "collapse",
"data-target" => ".navbar-collapse" ),
span1(
array( "class" => "sr-only" ),
"Toggle navigation"
)
);

Answer 3

Hello use below code for your desired output
function button1($attr, $text)
{
$data = "
foreach($attr as $names => $specs)
{
$data .= $names . "='" . $specs . "' ";
}
$data .= ">" . $text . "</button>\n";
return $data;
}
function span1($attr, $text)
{
$data = "<span ";
foreach($attr as $names => $specs)
{
$data .= $names . "='" . $specs . "' ";
}
$data .= ">" . $text . "</span>\n";
return $data;
}
$str = span1(
array( "class" => "sr-only" ),
"Toggle navigation"
);
echo button1(
array( "type" => "button",
"class" => "navbar-toggle",
"data-toggle" => "collapse",
"data-target" => ".navbar-collapse"
),
$str
);