First look at the example:
Copy Code code as follows:
<?php
$a = "Alsdflasdf;a";
$b = Var_dump ($a);
echo "<br>";
Var_dump ($c);
$d =var_dump ($c);
echo "<br>";
echo $a;
echo "<br>";
Echo $b;
echo "<br>";
Output:
String (a) "Alsdflasdf;a"
Null
Alsdflasdf;a
What does that mean? the Var_dump () method is to determine the type and length of a variable, and to output the value of the variable, if the variable has a value that loses the variable and returns the data type. This function displays information about the structure of one or more expressions, including the type and value of the expression. The array recursively expands the value and displays its structure by indenting it.
Its format: var_dump (mixed expression [, mixed expression [, ...]])
Look at the Var_dump syntax:
Var_dump (Var,var,bar);
Note that the variables inside the var_dump must be present, False if the variable exists but the value is empty, and NULL is returned if there is no variable. He has the function of outputting himself. You do not have to add other output functions.
