// 导入文件系统模块constfs=require('fs');// 判断目录是否存在的函数functioncheckDirectoryExists(dirPath){// 使用 fs.existsSync 检查目录if(fs.existsSync(dirPath)){console.log(`目录 "${dirPath}" 存在.`);returntrue;// 目录存在,返回 true}else{console.log(`目录 "${dirPath}" 不存在.`);ret...
//code to check if a value exists in an array using javascript for loop var fruits_arr = ['Apple', 'Mango', 'Grapes', 'Orange', 'Fig', 'Cherry']; function checkValue(value, arr) { var status = 'Not exist'; for (var i = 0; i < arr.length; i++) { var name = arr[...
Use some function to check if the value exists in an array of objects in JavaScript.someis a great function for checking the existence of things in arrays: JavaScript check if a value exists in an array of objects Simple example code. <!DOCTYPE html> const arr = [{ id: 1,...
AI代码解释 constarray=[3,8,12,6,10,2];// Find 10 in the given array.functioncheckForN(arr,n){for(leti=0;i<array.length;i++){if(n===array[i]){return`${true}${n}exists at index${i}`;}}return`${false}${n}does not exist in the given array.`;}checkForN(array,10); 这...
function f() { if (condition) { var tmp = ...; ... } // tmp still exists here // => not what we want } 如果要为then块引入新的作用域,可以定义一个函数并立即调用它。这是一种解决方法,模拟块作用域: function f() { if (condition) { (function () { // open block var tmp = ...
JavaScript check if variable exists (is definedinitialized) - We can use typeof operator to check the variable is defined or not.
constcache=newMap();functionresolve(file){constcached=cache.get(file);// A bit conservative: Check if the cached file still exists on disk to avoid// stale caches in watch mode where a file could be moved or be renamed.if(cached!==undefined&&isFile(file)){returncached;}// ...existin...
Type.define = function(name, check, override){ var Type = this; if(!Type.isStr(name) || !Type.isFunc(check)){ throw new TypeError('Param error'); }else if(!override && this.__defined__[name]){ throw new Error('Type ' + name + ' already exists'); ...
$("#run").on("click", () => tryCatch(run));asyncfunctionrun(){awaitExcel.run(async(context) => {// Add your Excel JavaScript API calls here.// Await the completion of context.sync() before continuing.awaitcontext.sync();console.log("Finished!"); }); }/** Default helper for ...
catch this filecount in javascript function. loop usingWhy are you counting through the files to check if a file exists? What would happen if the file server contained thousands of images?IMO it would be better to search for one image....