There are 4 common output statements in PHP: echo: output one or more values, separated by spaces. print: can only output one value. printf: You can format the output and use placeholders to specify the variable insertion position. var_dump: Outputs the value of a variable in a readable format, showing type, value, and structure.
Commonly used output statements in PHP
There are several commonly used output statements in PHP used on web pages Display information:
1. echo
echo
is the most basic output statement. It can output one or more values separated by spaces.
echo "Hello, world!";
2. print
print
is similar to echo
, but can only output one value.
print "Hello, world!";
3. printf
printf
can format the output. It takes a format string and one or more variables as arguments. The format string uses placeholders to specify where the variable should be inserted.
$name = "John Doe"; printf("Hello, %s!", $name); // 输出:Hello, John Doe!
4. var_dump
var_dump
Outputs the value of a variable in a readable manner, displaying the type, value and structure of the variable.
$array = [1, 2, 3]; var_dump($array); // 输出: // array(3) { // [0]=> // int(1) // [1]=> // int(2) // [2]=> // int(3) // }
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