Where can I read about conditionals done with "?" and ":" (colon)? [duplicate]
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Reference - What does this symbol mean in PHP?
I've been doing condi开发者_运维技巧tionals with if/else or a year or so now. Looking at some new code, I'm seeing a conditional that appears to use ?
and :
instead of if and else. I'd like to learn more about this, but I am not sure what to google to find articles explaining how it works. How can I do it?
It's the Ternary Operator.
Basic usage is something like
$foo = (if this expressions returns true) ? (assign this value to $foo) : (otherwise, assign this value to $foo)
It can be used for more than assignment though, it looks like other examples are cropping up below.
I think the reason you see this in a lot of modern, OO style PHP is that without static typing you end up needing to be paranoid about the types in any particular variable, and a one line ternary is less cluttered than a 7 line if/else conditional.
Also, in deference to the comments and truth in naming, read all about the ternary operators in computer science.
That would be the conditional operator. It's pretty much a single line if/then/else statement:
if(someCondition){
$x = doSomething();
}
else{
$x = doSomethingElse();
}
Becomes:
$x = someCondition ? doSomething() : doSomethingElse();
It is:
condition ? do_if_true : do_if_false
So, for example in the below, do->something() will be run.
$true = 1;
$false = 0
$true ? $do->something() : $do->nothing();
But in the below example, do->nothing() will be run.
$false ? $do->something() : $do->nothing();
This is the ternary operator in PHP. It's shorthand for if/else, format is:
condition ? true expression : false expression;
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