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Describe the differences between using `echo`, `print`, and `print_r` in php.
Describe the differences between using `echo`, `print`, and `print_r` in php.
Jul 12, 2025 am 02:15 AM
In PHP, echo, print, and print_r are used to output data but have different uses. 1. echo is used to quickly output one or more strings, with no return value, suitable for outputting plain text or string variables; 2. print is similar to echo but returns 1, and can be used as an expression, but has a slightly poor performance; 3. print_r is used for debugging, can output arrays and objects in an easy-to-read format, and can use the second parameter to decide whether to return the result instead of directly output.
In PHP, echo , print , and print_r are all used to output data, but they work differently and are suited for different scenarios. Here's how they compare.
1. echo – Fast and Simple Output
echo is the most common way to output strings in PHP. It's not actually a function, so you don't need parentses (though you can use them). It's fast and efficient.
- Outputs one or more strings
- Doesn't return a value
- Can take multiple arguments separated by commas
echo 'Hello', ' ', 'World'; // Outputs: Hello World
It's best used when you just want to print plain text or variables that are already strings.
2. print – Similar to echo , But With a Return Value
print works almost like echo , but with a few small differences:
- Only take one argument at a time
- Always returns 1 (which makes it technically an expression)
- Slightly slower than
echobecause of that return value
print "Hello World"; // Outputs: Hello World
Because of the return value, print can be used in expressions, which might come in handy in some edge cases. But in most situations, echo is preferred for performance and flexibility.
3. print_r – For Debugging Arrays and Objects
Unlike echo and print , print_r is meant for printing structured information in a human-readable format. It's especially useful when debugging.
- Prints arrays and objects in a readable format
- Accepts a second parameter to return the output instead of printing it
$array = ['name' => 'John', 'age' => 30]; print_r($array); // Output: // Array // ( // [name] => John // [age] => 30 // )
If you're trying to understand the structure of complex data, print_r is your go-to tool.
You can also capture the output into a variable by setting the second parameter to true :
$output = print_r($array, true);
This avoids directly printing it to the screen, which is helpful for logging or further processing.
Here's a quick comparison:
- Use
echofor fast string output - Use
printwhen you need an expression that returns a value (rarely needed) - Use
print_rwhen inspecting arrays or objects during development
Basically that's it.
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