te')); return $arr; } /* 遍历用户所有主题 * @param $uid 用户ID * @param int $page 页数 * @param int $pagesize 每页记录条数 * @param bool $desc 排序方式 TRUE降序 FALSE升序 * @param string $key 返回的数组用那一列的值作为 key * @param array $col 查询哪些列 */ function thread_tid_find_by_uid($uid, $page = 1, $pagesize = 1000, $desc = TRUE, $key = 'tid', $col = array()) { if (empty($uid)) return array(); $orderby = TRUE == $desc ? -1 : 1; $arr = thread_tid__find($cond = array('uid' => $uid), array('tid' => $orderby), $page, $pagesize, $key, $col); return $arr; } // 遍历栏目下tid 支持数组 $fid = array(1,2,3) function thread_tid_find_by_fid($fid, $page = 1, $pagesize = 1000, $desc = TRUE) { if (empty($fid)) return array(); $orderby = TRUE == $desc ? -1 : 1; $arr = thread_tid__find($cond = array('fid' => $fid), array('tid' => $orderby), $page, $pagesize, 'tid', array('tid', 'verify_date')); return $arr; } function thread_tid_delete($tid) { if (empty($tid)) return FALSE; $r = thread_tid__delete(array('tid' => $tid)); return $r; } function thread_tid_count() { $n = thread_tid__count(); return $n; } // 统计用户主题数 大数量下严谨使用非主键统计 function thread_uid_count($uid) { $n = thread_tid__count(array('uid' => $uid)); return $n; } // 统计栏目主题数 大数量下严谨使用非主键统计 function thread_fid_count($fid) { $n = thread_tid__count(array('fid' => $fid)); return $n; } ?>JavaScript Switch Statements - possible to use case value? - Stack Overflow

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    JavaScript Switch Statements - possible to use case value? - Stack Overflow

    programmeradmin4浏览0评论

    I was wondering if it is possible to use something similar to 'this' in a Javascript switch statement when executing blocks of code.

    For example:

    switch(x) {
    case 'The pyramids of Giza':
        console.log(this);
        break;
    case 'The Leaning Tower of Pisa':
        console.log(this);
        break;
    default:
        console.log('Not found');
}

    Is the same as:

    switch(x) {
    case 'The pyramids of Giza':
        console.log('The pyramids of Giza');
        break;
    case 'The Leaning Tower of Pisa':
        console.log('The Leaning Tower of Pisa');
        break;
    default:
        console.log('Not found');
}

    This is purely just for efficiency purposes, thanks!

    I was wondering if it is possible to use something similar to 'this' in a Javascript switch statement when executing blocks of code.

    For example:

    switch(x) {
    case 'The pyramids of Giza':
        console.log(this);
        break;
    case 'The Leaning Tower of Pisa':
        console.log(this);
        break;
    default:
        console.log('Not found');
}

    Is the same as:

    switch(x) {
    case 'The pyramids of Giza':
        console.log('The pyramids of Giza');
        break;
    case 'The Leaning Tower of Pisa':
        console.log('The Leaning Tower of Pisa');
        break;
    default:
        console.log('Not found');
}

    This is purely just for efficiency purposes, thanks!

    • javascript
    • switch-statement
    Share Improve this question asked Aug 22, 2015 at 13:15 Domenic CorsoDomenic Corso 551 silver badge10 bronze badges 2
    • 4 Just use x in the code between the case and the break. Longer explanation ing up! – Noble Mushtak Commented Aug 22, 2015 at 13:16
    • Thanks for the quick reply, just discovered that I am an idiot because if it's the same value I would just use x! – Domenic Corso Commented Aug 22, 2015 at 13:18
    Add a ment  | 

    4 Answers 4

    Reset to default 14

    You have access to the variable that you're testing within the switch statement; after all, if x is equal to "The pyramids of Giza", then x must also be the value you wish to use within that case.

    switch(x) {
    case 'The pyramids of Giza':
        console.log(x); // output: 'The pyramids of Giza'
        break;
    case 'The Leaning Tower of Pisa':
        console.log(x); // output: 'The Leaning Tower of Pisa'
        break;
    default:
        console.log('Not found');
}

    When you visit a case:, the value of the value specified in the case: is always the variable put in the switch statement. This is because a case: is only visited if the variable is equal to the value specified in case: in the first place, so you know that if you've visited that case, then the value of the variable must be the same as the value specified in the case:. Thus, this is the code you're looking for:

    switch(x) {
    case 'The pyramids of Giza':
        console.log(x);
        break;
    case 'The Leaning Tower of Pisa':
        console.log(x);
        break;
    default:
         console.log('Not found');
}

    switch(x) {
    case 'The pyramids of Giza':
        console.log(x);
        break;
    case 'The Leaning Tower of Pisa':
        console.log(x);
        break;
    default:
        console.log('Not Found');
}

    Should do the trick

    If you are returning the value in HTML you can write it like this

    switch(x) {
    case 'The pyramids of Giza':
        return `<button class="badge text-white">${x}</button>`
        break;

    case 'The Leaning Tower of Pisa':
        return `<button class="badge text-blue">${x}</button>`
        break;
    default:
        console.log('Not Found');
}

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