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Home Backend Development PHP Tutorial 代码编程规范之逻辑判断疑问?

代码编程规范之逻辑判断疑问?

Jun 06, 2016 pm 08:08 PM
c c++ java php

代码编程规范之逻辑判断疑问?

我想问一下各位大大,像这样的逻辑判断避免不了,可是又好像太繁琐,以代码编程规范为参考,如何优化或者规避这样的现象呢?

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代码编程规范之逻辑判断疑问?

我想问一下各位大大,像这样的逻辑判断避免不了,可是又好像太繁琐,以代码编程规范为参考,如何优化或者规避这样的现象呢?

经验问题。单独来说if(!is_array)这段吧,这可能来自以下需求:
咱们啊有个数,然后想和另一个比较,另一个是什么呢,可以随便输入,但是肯定是大于5,小于7,大约等于8,小于等于10这种,你给做一下吧。
然后你就这么做了,没有错。
因为不懂开发的人会实事求是的描述他的需求,但是我认为开发人员应该有自己的理解,比如我会抽象为:
将数字A与期望的表达式B比对,并得到结果;其中,表达式B包含操作符与操作数两部分。即,表达式B应该符合正则表达式 /^([^\d]+)(\d+)$/;其中$1是操作符,$2是操作数。且,操作符必须是 ,>=之一。
这样,代码将类似

<code>//$a 操作数A, $b, 表达式B,$c, 操作符, $n2 第二个操作数
if (! preg_match('/^\d+$/', $a)) {
    die('a无效');
}
if (! preg_match('/^([^\d]+)(\d+)$/', $b, $_match)) {
    die("格式错误");
}
$c = $_match[1][0];
$n2 = $_match[1][1];
$useableC = array('', '>=');
if (! in_array($c, $useableC)) {
    die('无效的操作符');
}
eval("\$t = $a $c $n2");
if ($t) echo 'Y';
echo echo 'N';</code>
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很明显,这样你可以很容易的扩展到更多的操作符,以后想增加==,!=很方便。
以上是伪码,不建议使用正则表达式作为数字有效性验证的最终标准

写作能力很差,不知道你能明白我想表达的意思不,希望有帮助。

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