php if else syntax of process control
if and else grammar
This is a very important section is also an important PHP syntax among.
[Note] I define the level of this syntax is: dictation level. That is you need, eyes closed, we are able to write something. Linear motor parameters
English explanation:
* if * pronunciation: [ɪf]
Chinese explanation: if
else pronunciation: [ɛls]
Chinese explanation: otherwise
We will if and if ... else combined into four basic grammar, each of which must back down.
<? PHP IF (Boolean condition) to perform a Boolean value is true (true), can only write a single line of code; ?> <PHP? IF (Boolean condition) to perform a Boolean value is true (true), can only write one line of code; else perform a Boolean value false (false), you can only write a single line of code; ?>
<PHP?
IF (Boolean condition) {
executes boolean value True (true), write lines of code;
}
?>
<PHP?
IF (Boolean condition) {
executes boolean value True (true), a multi-writable line;
} {the else
performs the Boolean value false (false), write lines of code;
}
>?
Many people like to buy lottery tickets, we take the process Gambling show to write if example.
? <PHP
// definition of what winning variable, the variable is true, represent a winning
$ zhongjiang = to true;
// Since $ zhongjiang result is true, it shows: "buy a house"
// be changed to try false execution result, if false, then, does not perform echo 'buy a house';
IF ($ Zhongjiang) {
echo 'buy a house';
}
// succeeding code
echo 'why why';
?>
In the "Book of Changes 3.2.2 Boolean is knowledge" with you to make this chapter a wretched example:
For example television drama series often talk about the sentence:
If the beautiful sister (guy) is my bubble at hand, I'm dead willing.
We take a look at is the flow chart look like this:
You can write this sentence with the code of the computer:
If I soak into the beautiful sister
is: I am willing to die
if there is no bubble to
you: I do not want to die
If you press the flowchart of view, then is this:
The above example, we can use if ... else ... translated into code:
? <PHP // we define a bubble to the beauty of the variable ($ pao) is false, meaning no bubble to $ PAO = false; IF ($ pao) // you can try here to write multiple lines of code will not error. echo 'I am willing to die'; the else echo 'I do not want to die'; //if...else execution ends, follow the code ?> in the if ...
else, we can write a use braces, multiple words example:
? <PHP
// we define a bubble to the beauty of the variable ($ pao) is true, meaning the bubble to
$ PAO = to true;
IF ($ pao) {
echo 'I am willing to die';
echo 'Lin Chi-ling, I love is you. ';
} The else {
echo' I do not want to die ';
echo' Xifeng, I would not love you ';
}
//if...else execution ends, subsequent code
>?