Shulou(Shulou.com)06/03 Report--

This article mainly explains "detailed explanation of operators in PHP". The content of the explanation in the article is simple and clear, and it is easy to learn and understand. Please follow the editor's train of thought to study and learn "detailed explanation of operators in PHP".

What is an operator?

What is an operator? Operators are identifiers that tell PHP to do related operations. For example, if you need to calculate how much 123 times 456 equals, you need a symbol to tell the server that you need to multiply.

What are the operators in PHP? PHP operators are generally divided into arithmetic operators, assignment operators, comparison operators, ternary operators, logical operators, string concatenation operators, and error control operators.

Arithmetic operators in PHP

Arithmetic operators are mainly used for arithmetic operations, such as addition, subtraction, multiplication and division. The common arithmetic operators in PHP correspond to the following table:

Assignment operator in PHP

There are two assignment operators for PHP, which are:

(1) "=": assign the value of the expression on the right to the Operand on the left. It makes a copy of the expression value on the right and gives it to the Operand on the left. In other words, first apply a piece of memory for the Operand on the left, and then put the copied value in this memory.

(2) "&": reference assignment, meaning that both variables point to the same data. It will make the two variables share a piece of memory, and if the data stored in this memory changes, then the values of both variables will change.

Comparison operator in PHP

Comparison operators are mainly used for comparison operations, such as equal, congruent, unequal, greater than and less than. The comparison operators commonly used in PHP are shown in the following table:

Ternary operators in PHP

The ternary operator is also a comparison operator. For the expression (expr1)? (expr2): (expr3), if the value of expr1 is true, the value of the expression is expr2, otherwise it is expr3.

Logical operators in PHP

The main use of logical operators is to perform logical operations, such as logical and, logical OR, logical XOR, logical non, and so on. The logical operators commonly used in PHP are shown in the following table:

We can understand logical operations from the perspective of voting:

1. Logic and: everyone is required to vote in order to pass an agreement.

2. Logical OR: only one person is required to vote for it

3. Logical XOR: only one person can vote for it.

4. Logical wrong: someone wants to object, but through logical wrong, make his objection invalid.

The reason why there are two different forms of operators for "and" or is the priority of their operations (that is, the limited order of operations, for example, when we learned four operations in primary school, we mixed addition, subtraction, multiplication and division, and then calculated addition and subtraction).

We can understand logical operations from the perspective of voting:

1. Logic and: everyone is required to vote in order to pass an agreement.

2. Logical OR: only one person is required to vote for it

3. Logical XOR: only one person can vote for it.

4. Logical wrong: someone wants to object, but through logical wrong, make his objection invalid.

String concatenation operators in PHP

String concatenation operators are used to concatenate two strings. The string concatenation operators provided in PHP are:

(1) concatenation operator ("."): it returns the string that appends the right argument to the left argument.

(2) concatenation assignment operator (". ="): it appends the parameter on the right to the parameter on the left.

Error control operators in PHP

An error control operator "@" is provided in PHP. For expressions that may go wrong during the run, we do not want to display an error message to the customer when something goes wrong, which is not user-friendly. Therefore, @ can be placed before an PHP expression, and any error messages that may be generated by that expression are ignored

If the track_error (which is set in php.ini) feature is activated, any error messages generated by the expression are stored in the variable $php_errormsg, which is overwritten every time an error occurs, so you must check it as soon as possible if you want to use it.

It is important to note that the error control prefix "@" does not mask parsing errors, cannot be placed before the definition of a function or class, and cannot be used in conditional structures such as if and foreach.

Thank you for your reading, the above is the content of "detailed interpretation of operators in PHP". After the study of this article, I believe you have a deeper understanding of the detailed interpretation of operators in PHP, and the specific use needs to be verified in practice. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.