The some() method tests whether at least one element in an array passes a certain position. If the array is empty, the some() method returns false, Here’s an example: const myArray = []; if (myArray.some(item => item !== null)) { console.log('Array is not empty'); } else...
校验数组是否为空 const isNotEmpty = arr => Array.isArray(arr) && arr.length > 0; console.log(isNotEmpty([1, 2, 3])); // Result: true console.log(isNotEmpty([])); // Result: false 1. 2. 3. 4. 5.
方法一 Array.isArray && arr.length 通过Array.isArray来判断是否为数组,再通过length属性。...它还检查数组是否未定义或为空。 可以使用array.length属性检查数组是否为空。此属性返回数组中的元素数。如果数字大于0,则计算结果为true。...此方法和属性可与and(&&)运算符一起使用,以确定数组是否存在且不为空。
在项目中,我们用的最多的是StringUtils中的非空判断方法,相信大部分人都用过IsNotEmpty或者 isEmpty方法 public static boolean isNotEmpty(String...str) 判断某字符串是否非空,等于!...StringUtils.isNotEmpty("bob") ...
Note that in the default configuration, without setting runScripts, the values of window.Array, window.eval, etc. will be the same as those provided by the outer Node.js environment. That is, window.eval === eval will hold, so window.eval will not run scripts in a useful way. We str...
post.capabilities.items仍然会被定义，因为它是一个空数组，如果你检查post.capabilities.items.length，它...
apply if condition -if (2 > 3); +if (2 > 3) alert();apply isArray() -x instanceof Array; +Array.isArray(x);apply Array.at() -const latest = (a) => a[a.length - 1]; +const latest = (a) => a.at(-1);apply optional chaining (proposal-optional-chaining) -const ...
bodyBodyInit(optional)HTTP response body as one ofArrayBuffer,AsyncIterable<Uint8Array>,Blob,FormData,Iterable<Uint8Array>,NodeJS.ArrayBufferView,URLSearchParams,null, orstring. jsonBodyany(optional)A JSON-serializable HTTP Response body. If set, theHttpResponseInit.bodyproperty is ignored in favor ...
on property is used to bind a function with the event and emit is used to fire an event.MethodsSr.No.Method & Description 1 addListener(event, listener) Adds a listener at the end of the listeners array for the specified event. No checks are made to see if the listener has already ...
isEmpty() iterator()returns the same astoArray()because it is iterable and follows Java's implementation. Barely useful. Usefor (const value of heap)instead. offer(element)alias ofadd(element) peek() poll()alias ofpop() remove(element?) ...