��权限没有,则隐藏 function forum_list_access_filter($forumlist, $gid, $allow = 'allowread') { global $grouplist; if (empty($forumlist)) return array(); if (1 == $gid) return $forumlist; $forumlist_filter = $forumlist; $group = $grouplist[$gid]; foreach ($forumlist_filter as $fid => $forum) { if (empty($forum['accesson']) && empty($group[$allow]) || !empty($forum['accesson']) && empty($forum['accesslist'][$gid][$allow])) { unset($forumlist_filter[$fid]); } unset($forumlist_filter[$fid]['accesslist']); } return $forumlist_filter; } function forum_filter_moduid($moduids) { $moduids = trim($moduids); if (empty($moduids)) return ''; $arr = explode(',', $moduids); $r = array(); foreach ($arr as $_uid) { $_uid = intval($_uid); $_user = user_read($_uid); if (empty($_user)) continue; if ($_user['gid'] > 4) continue; $r[] = $_uid; } return implode(',', $r); } function forum_safe_info($forum) { //unset($forum['moduids']); return $forum; } function forum_filter($forumlist) { foreach ($forumlist as &$val) { unset($val['brief'], $val['announcement'], $val['seo_title'], $val['seo_keywords'], $val['create_date_fmt'], $val['icon_url'], $val['modlist']); } return $forumlist; } function forum_format_url($forum) { global $conf; if (0 == $forum['category']) { // 列表URL $url = url('list-' . $forum['fid'], '', FALSE); } elseif (1 == $forum['category']) { // 频道 $url = url('category-' . $forum['fid'], '', FALSE); } elseif (2 == $forum['category']) { // 单页 $url = url('read-' . trim($forum['brief']), '', FALSE); } if ($conf['url_rewrite_on'] > 1 && $forum['well_alias']) { if (0 == $forum['category'] || 1 == $forum['category']) { $url = url($forum['well_alias'], '', FALSE); } elseif (2 == $forum['category']) { // 单页 $url = ($forum['threads'] && $forum['brief']) ? url($forum['well_alias'] . '-' . trim($forum['brief']), '', FALSE) : url($forum['well_alias'], '', FALSE); } } return $url; } function well_forum_alias() { $forumlist = forum_list_cache(); if (empty($forumlist)) return ''; $key = 'forum-alias'; static $cache = array(); if (isset($cache[$key])) return $cache[$key]; $cache[$key] = array(); foreach ($forumlist as $val) { if ($val['well_alias']) $cache[$key][$val['fid']] = $val['well_alias']; } return array_flip($cache[$key]); } function well_forum_alias_cache() { global $conf; $key = 'forum-alias-cache'; static $cache = array(); // 用静态变量只能在当前 request 生命周期缓存,跨进程需要再加一层缓存:redis/memcached/xcache/apc if (isset($cache[$key])) return $cache[$key]; if ('mysql' == $conf['cache']['type']) { $arr = well_forum_alias(); } else { $arr = cache_get($key); if (NULL === $arr) { $arr = well_forum_alias(); !empty($arr) AND cache_set($key, $arr); } } $cache[$key] = empty($arr) ? '' : $arr; return $cache[$key]; } ?>javascript - ERR_UNHANDLED_REJECTION UnhandledPromiseRejection when awaited inside an array of promise Objects - Stack Overflow
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javascript - ERR_UNHANDLED_REJECTION UnhandledPromiseRejection when awaited inside an array of promise Objects - Stack Overflow

programmeradmin5浏览0评论

I am trying to understand async await with promises and for..of loop. I have a function which generates promise by resolving if an even number is passed to it and by rejecting if odd number is passed to it. Inside an async function I am tying to await but getting UnhandledPromiseRejection even though I am catching the error. My question is what points i am missing. Why I am getting UnhandledPromiseRejection and how to handle it. I need conceptual information

function genPromise(value) {
    return new Promise((resolve, reject) => {
        if (value % 2) {
            resolve(`The value ${value} is odd`);
        } else {
            reject(`The value ${value} is even`);
        }
    })
}

(async function () {

    x = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
    let y = x.map(d => genPromise(d))
    try {
        for await (let k of y) {
            console.log(k);
        }
    } catch (err) {
        console.log(err)
    }
})();

I am trying to understand async await with promises and for..of loop. I have a function which generates promise by resolving if an even number is passed to it and by rejecting if odd number is passed to it. Inside an async function I am tying to await but getting UnhandledPromiseRejection even though I am catching the error. My question is what points i am missing. Why I am getting UnhandledPromiseRejection and how to handle it. I need conceptual information

function genPromise(value) {
    return new Promise((resolve, reject) => {
        if (value % 2) {
            resolve(`The value ${value} is odd`);
        } else {
            reject(`The value ${value} is even`);
        }
    })
}

(async function () {

    x = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
    let y = x.map(d => genPromise(d))
    try {
        for await (let k of y) {
            console.log(k);
        }
    } catch (err) {
        console.log(err)
    }
})();
Share Improve this question edited Feb 2, 2022 at 13:24 Ibnjunaid asked Jun 21, 2021 at 5:34 IbnjunaidIbnjunaid 5121 gold badge6 silver badges15 bronze badges
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2 Answers 2

Reset to default 4

for await( is only intended for use with async iterables. You do not have an async iterable - only a normal iterable, in which case it's equivalent to for..of:

for (const k of y) {
  console.log(k);
}

The k promise is not being caught, hence the rejection.

Await k inside the loop, without for await:

function genPromise(value) {
    return new Promise((resolve, reject) => {
        if (value % 2) {
            resolve(`The value ${value} is odd`);
        } else {
            reject(`The value ${value} is even`);
        }
    })
}

(async function () {

    x = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
    let y = x.map(d => genPromise(d))
    try {
        for (const k of y) {
            console.log(await k);
        }
    } catch (err) {
        console.log('error', err)
    }
})();

If you wanted to make an async iterable from the array of numbers, then you'd do something like:

function* genPromise(arr) {
    for (const value of arr) {
        yield new Promise((resolve, reject) => {
            if (value % 2) {
                resolve(`The value ${value} is odd`);
            } else {
                reject(`The value ${value} is even`);
            }
        });
    }
}

(async function () {
    const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
    try {
        for await (const k of genPromise(arr)) {
            console.log(k);
        }
    } catch (err) {
        console.log('error', err)
    }
})();

if you want to check all the numbers without to stop in the first time that you have an even number, you need clear the reject

function* genPromise(arr) {
    for (const value of arr) {
        yield new Promise((resolve, reject) => {
            if (value % 2) {
                resolve(`The value ${value} is odd`);
            } else {
                resolve(`The value ${value} is even`);
            }
        });
    }
}

(async function () {
    const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
    try {
        for await (const k of genPromise(arr)) {
            console.log(k);
        }
    } catch (err) {
        console.log('error', err)
    }
})();

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