What are the uses of php curly braces
What are the uses of php curly braces? for this question, this article introduces in detail the corresponding analysis and answers, hoping to help more partners who want to solve this problem to find a more simple and feasible way.
There are many uses of php curly braces, such as: 1, "function name () {}" or "for () {}" usage; 2, "$str {4}" usage; 3, "{$val}" usage.
This article operating environment: windows7 system, PHP7.1 version, DELL G3 computer
What is the use of php curly braces?
PHP's curly braces (curly braces {}) are explained in detail
No matter what program, function name () {}, for () {}, … . It's too much. I don't have to say it.
Second, $str {4} treats a string variable as an array after the {} curly braces and square braces [].
3. {$val} this is the problem I encountered, and the role of curly braces is to tell PHP that what is enclosed should be treated as a variable.
Examples are as follows:
/ / The following is okay as it's inside a string. Constants are not//looked for within strings so no E_NOTICE error hereprint "Hello $arr [fruit]"; / / Hello apple//With one exception, braces surrounding arrays within strings//allows constants to be looked forprint "Hello {$arr [fruit']}"; / / Hello carrotprint "Hello {$arr ['arr]}"; / / Hello apple
Also: the role of curly braces (curly braces {}) in PHP string variables
The PHP variable is followed by a curly bracing {}, filled with a number, which refers to the character of the corresponding sequence number of the PHP variable.
For example:
$str = 'hello'
Echo $str {0}; / / output as h, or $str [0] echo $str {1}; / / output as e, or $str [1]
If you want to check whether a string satisfies a certain length, you can consider replacing the strlen function with curly braces (curly braces) plus isset. Because isset is a language structure and strlen is a function, using isset is more efficient than using strlen.
For example, determine whether the length of a string is less than 5:
The answers to the questions about the use of php curly braces are shared here. I hope the above content can be of some help to you. If you still have a lot of doubts to be solved, you can follow the industry information channel for more related knowledge.
