The mysteries of auto-increment and auto-increment operations in PHP _ PHP Tutorial

The mysteries of the auto-increment and auto-increment operations in PHP. First, let's take a look at the questions about the auto increment and auto increment operations in PHP: $ a1; $ B $ a; if ($ B $ a ++) echotrue; elseechofalse; first, creates a variable $ a and describes the mysteries of the auto-increment and auto-increment operations in PHP.

First, let's take a look at the interview question:

$ A = 1; $ B = & $ a; if ($ B = $ a ++) echo "true"; else echo "false ";

First, create a variable $ a and set the value to 1;

Then, a variable $ B is created and used as a reference to $;

Finally, this judgment statement contains two Opcodes: POST_INC and IS_EQUAL. First, the Post-auto-increment statement (POST_INC) is executed. first, 1 is returned, and then $ a is auto-incremented to 2 because $ B is a reference of $, $ B is also 2. The comparison statement (IS_EQUAL) is executed, because the value of $ B is 2, and the return value of $ a ++ is 1, so they are not equal.

Similar interview questions include:

$ A = 1; $ B = & $ a; $ B = $ a ++; echo "a: $ a; B: $ B ";

Else first take a look at an interview question: $ a = 1; $ B = $ a; if ($ B = $ a ++) echo "true"; else echo "false "; first, create a variable $ a and...