This question already has an answer here: JavaScript Hashmap Equivalent 17 answers Don't use an array if you want named keys, use a plain object. var a = {}; a["key1"] = "value1"; a["key2"] = "value2"; Then: if ("key1" in a) { // something } else { // something else } A built-in Map type is now available in JavaScript. It can be used instead of simply using Object. It is supp
这个问题在这里已经有了答案： JavaScript哈希表等效17个答案 如果您想要命名键，请不要使用数组，如果使用普通对象。 var a = {}; a["key1"] = "value1"; a["key2"] = "value2"; 然后： if ("key1" in a) { // something } else { // something else } JavaScript中现在提供了内置的Map类型。 它可以用来代替简单地使用Object。 它受到所有主流浏览器的当前版本的支持。 地图不支持Objects使用的[subscript]
amt: "10.00" email: "sam@gmail.com" merchant_id: "sam" mobileNo: "9874563210" orderID: "123456" passkey: "1234" The above is the JSON object I'm dealing with. I want to check if the 'merchant_id' key exists. I tried the below code, but it's not working. Any way to achieve it? <script> window.onload = function getApp() { var thisSession = JSON.parse('<?php echo json_
amt: "10.00" email: "sam@gmail.com" merchant_id: "sam" mobileNo: "9874563210" orderID: "123456" passkey: "1234" 以上是我正在处理的JSON对象。 我想检查'merchant_id'键是否存在。 我尝试了下面的代码，但它不工作。 任何方式来实现它？ <script> window.onload = function getApp() { var thisSession = JSON.parse('<?php echo json_encode($_POST); ?>'); //console.log(thisSession); i
I have 2 nested objects which are different and I need to know if they have difference in one of their nested properties. var a = {}; var b = {}; a.prop1 = 2; a.prop2 = { prop3: 2 }; b.prop1 = 2; b.prop2 = { prop3: 3 }; The object could be much more complex with more nested properties. But this one is a good example. I have the option to use recursive functions or something with lodash...
我有2个不同的嵌套对象，我需要知道他们的嵌套属性是否有差异。 var a = {}; var b = {}; a.prop1 = 2; a.prop2 = { prop3: 2 }; b.prop1 = 2; b.prop2 = { prop3: 3 }; 对象可能更复杂，嵌套属性更多。 但这是一个很好的例子。 我可以选择使用递归函数或lodash ... 一个简单而优雅的解决方案是使用_.isEqual进行深入比较： var a = {}; var b = {}; a.prop1 = 2; a.prop2 = { prop3: 2 }; b.prop1 = 2; b.prop2 = { p
This question already has an answer here: Checking if a key exists in a JavaScript object? 16 answers How do I check if an object has a property in JavaScript? 22 answers
这个问题在这里已经有了答案： 检查JavaScript对象中是否存在关键字？ 16个答案 如何检查一个对象是否在JavaScript中有属性？ 22个答案
This question already has an answer here: Checking if a key exists in a JavaScript object? 16 answers Use the hasOwnProperty call if (!obj.hasOwnProperty(key)) { } https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty 你可以这样做： var key = 'key1'; if (!('key1' in obj)) { .... } // or if (!(key in obj)) { }
这个问题在这里已经有了答案： 检查JavaScript对象中是否存在关键字？ 16个答案 使用hasOwnProperty调用 if (!obj.hasOwnProperty(key)) { } https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty 你可以这样做： var key = 'key1'; if (!('key1' in obj)) { .... } // or if (!(key in obj)) { }
I'm passing an async function to an array reduce function. What's the syntax for catching errors thrown by the passed in function? The reducing is happening inside a try catch block, which is catching other errors just fine, but node gives me an UnhandledPromiseRejectionWarning if the passed in function itself throws an error. Code: aFunction = async (anArray) => { try { con
我将一个async函数传递给数组reduce函数。 捕获传入函数抛出错误的语法是什么？ 减少发生在一个try catch块内，它正好捕获其他错误，但是如果传入的函数本身抛出一个错误，节点会给我一个UnhandledPromiseRejectionWarning 。 码： aFunction = async (anArray) => { try { const result = await anArray.reduce(async (a, b) => { await doSomethingTo(b); }, Promise.resolve()); return resul
I want to know if a string starts with the specified character/string or ends with it in jQuery. For Example: var str = 'Hello World'; if( str starts with 'Hello' ) { alert('true'); } else { alert('false'); } if( str ends with 'World' ) { alert('true'); } else { alert('false'); } If there is not any function then any alternative ? 一种选择是使用正则表达式： if (str.match("^Hell
我想知道一个字符串是以指定的字符/字符串开头还是以jQuery结尾。 例如： var str = 'Hello World'; if( str starts with 'Hello' ) { alert('true'); } else { alert('false'); } if( str ends with 'World' ) { alert('true'); } else { alert('false'); } 如果没有任何功能，那么有其他选择吗？ 一种选择是使用正则表达式： if (str.match("^Hello")) { // do this if begins with Hello } if (str.mat
I can't post my company's proprietary code, but here is some concept code that should get the point across. It may not be free of syntax errors. Server 1: PHP 5.3.5 , php.ini magic_quotes_gpc = On (default) On this server we render a page using PHP. The page has a button with JavaScript attached to the click event. The JavaScript posts to a URL on a second server, something like th
我无法发布我公司的专有代码，但这里有一些概念代码应该能够说明问题。 它可能没有语法错误。 服务器1：PHP 5.3.5 ，php.ini magic_quotes_gpc = On （默认） 在这个服务器上，我们使用PHP呈现一个页面。 该页面有一个JavaScript附加到click事件的按钮。 JavaScript发布到第二台服务器上的URL，如下所示： var myURL = "http://server2/AcceptPacket"; var POSTdata = getElementById("JSONdata"); var responsetext = ht
This question already has an answer here: Encode URL in JavaScript? 12 answers Using decodeURIComponent() The decodeURIComponent() function decodes a Uniform Resource Identifier (URI) component previously created by encodeURIComponent or by a similar routine. var decodedStr = decodeURIComponent('%D0%9F%D1%80%D0%B8%D0%B2%D0%B5%D1%82') console.log(decodedStr);
这个问题在这里已经有了答案： 在JavaScript中编码URL？ 12个答案 使用decodeURIComponent() decodeURIComponent（）函数解码先前由encodeURIComponent或类似例程创建的统一资源标识符（URI）组件。 var decodedStr = decodeURIComponent('%D0%9F%D1%80%D0%B8%D0%B2%D0%B5%D1%82') console.log(decodedStr);
This question already has an answer here: Encode URL in JavaScript? 12 answers Instead of escape use encodeURI . The escape() function was deprecated in JavaScript version 1.5. What is the difference? escape — broken, deprecated, do not use, encodes all the characters. encodeURI — encodes characters that are not allowed (raw) in URLs (use it to fix up broken URIs if you can't fix
这个问题在这里已经有了答案： 在JavaScript中编码URL？ 12个答案 而不是escape使用encodeURI 。 escape（）函数在JavaScript 1.5版中已弃用。 有什么不同？ escape - 破碎，弃用，不使用，编码所有字符。 encodeURI - 对URL中不允许的（原始）字符进行编码（如果您无法事先修复它们，请使用它修复损坏的URI）