PHP is a very popular programming language and for many developers, it is one of the first choices for building dynamic websites and web applications. In PHP, symbols are the basis of the language and can help you implement complex functions. To this end, this article will introduce you to the use of symbols in PHP.
- Variable symbols
You need to use the $ symbol before the variable name in PHP, as shown below:
$variableName = 'Hello World!'; echo $variableName;
Through the above code , we can store the string 'Hello World!' in the $variableName
variable and use the echo
statement to output it to the Web page.
- Array notation
In PHP, square brackets ([]) represent arrays. Here is an example of creating an array:
$fruits = ['apple', 'banana', 'orange'];
We can use array indexing to access data:
echo $fruits[0]; //输出'apple'
- Function symbols
In PHP, the function name followed by parentheses is equivalent to executing the function, as shown below:
echo strlen('Hello World!');
The output result of the above code is: 11, which is the number of characters in the string 'Hello World!'.
- Operation symbols
supports various operators in PHP, such as arithmetic operators, logical operators, comparison operators, etc. The following is an example:
$x = 10; $y = 5; echo $x + $y; //输出15 echo $x - $y; //输出5 echo $x * $y; //输出50 echo $x / $y; //输出2 echo $x % $y; //输出0 echo $x > $y; //输出1 echo $x <ol start="5"><li><strong>Control structure symbols</strong></li></ol><p>Control structure symbols in PHP include if/else, switch and loop structures, etc. The following is an example of using an if/else statement: </p><pre class="brush:php;toolbar:false">$x = 10; $y = 5; if ($x > $y) { echo 'x is greater than y'; } else { echo 'y is greater than x'; }
The output result is: 'x is greater than y', because the value of $x is greater than $y.
- Comment symbols
In PHP, you can use double slashes (//) to add single-line comments. An example is as follows:
//这是一个单行注释
If you need to add a multi-line comment, you can surround your comment with slash asterisks (/ /). Examples are as follows:
/* 这是一个 多行注释 */
The above are commonly used symbols in PHP, and they help us complete many tasks easily. I hope the introduction in this article will be helpful for you to learn PHP!
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