Powerpoint2007 official download What is the difference between echo, print and print_r?

echo is a PHP statement, print and print_r are functions, statements have no return value, and functions can have return values ​​(even if they are useless)
print can only print out the values ​​of simple type variables (such as int, string)
print_r can print out complex types The value of the variable (such as array, object)
echo -- Output one or more strings
Description
void echo ( string arg1 [, string ...] ) //The return value is empty
echo "Hello"," Friend";
print -- Output a string
Description
int print (string arg)//The return value is an integer
print "Hello friend";
You can perform the following operations
$name=print "nihao n";
$str = 'test print value is $name .';
eval("$print="$str";");
echo $print;
print_r -- Print easy-to-understand information about the variable.
bool print_r (mixed expression [, bool return] ) //The return value is Boolean, the parameter is of mix type, which can be a string, an integer, an array, or an object class. Print_r() displays easy-to-understand information about a variable. . If a string, integer or float is given, the variable value itself will be printed. If an array is given, the keys and elements will be displayed in a certain format. object is similar to an array.
print_r() will move the array pointer to the end.
You can
print_r(str);
print_r(int);
print_r(array);
print_r(obj);
You can also use var_dump var_export

The above introduces the difference between echo, print and print_r of powerpoint2007 official download? , including the official download of powerpoint2007, I hope it will be helpful to friends who are interested in PHP tutorials.