TypeError: This is undefined – ReactJS, Javascript
1> Aluan Haddad..: a) this is created using arrow functions in the instance ( ) on a lexically closed attribute, or b) using .bind. Do one or the other. a) class Layer5 extends React.Component { constructor(props) { super(props); this.handleClick = e => { e.preventDefault(); this.setState({buttonstate: !this.state.buttonstate}); }; } } or b) render() { const icon = this.state.buttonstate ? ‘images/image1.png’ : ‘images/image2.jpg’; return ; } }
Add multiple objects using object spread operator (ES6, JavaScript)
javascript object java ip Write your review! Come on, watch it all Member login | User registration Recommended reading ip jQuery animation: ignore styling with css – jQuery animation: ignore styling with css WhenIamdoinganimationwithjQuery(like$(.myClass).slideDown())itaddssomestylesinlineto … [detailed] Crayon Shin-chan 2023-09-25 16:07:05 ip Bcrypt binding error. Module not registering itself? – Bcrypt Binding Error. Module did not self register? SoImtryingtorunmyMEANstackappagainandwhenIenternodeserver.js,Igeterror: So I’m trying to run again… [detailed] Crayon Shin-chan 2023-09-25 16:12:23
Java’s support for scripting languages (such as: ruby, groovy, javascript)
This article explains the Scripting API Scripting API is an API used to write scripting language programs in Java. The Scripting API can be found in Javax.script. We use this API to write Javascript programs. There is a ScriptEngineManager class in this package, which uses Scriptng At the entrance of the API, ScriptEngineManager can find the appropriate script engine class (ScriptEngine) through the Jar service discovery (service discovery) mechanism. The simplest way to use the Scripting API only requires the following three steps1. Create A ScriptEngineManagerobject2. Obtain the ScriptEngine object through ScriptEngineManager3. Use the eval method of ScriptEngine to execute the script Sample code: import javax.script.Invocable; import javax.script.ScriptEngine; import javax.script.ScriptEngineManager; public class Test { public static void main(String[] args){ ScriptEngineManager factory = new ScriptEngineManager(); ScriptEngine engine = factory.getEngineByName(“Javascript”); String script; try { script = “print(‘Hello’)”; engine.eval(script);//Execute script script = “1-23*9/3+77”; System.out.println(engine.eval(script).toString());//You can get the calculation result without parsing the string engine.put(“a”, “a string”); script = “print(a)”; engine.eval(script);//The script calls the java object script = “function hello(name) { return ‘Hello,’ + name;}”; engine.eval(script); Invocable inv = (Invocable) engine; System.out.println(inv.invokeFunction(“hello”, “Scripting”));//java calls script method } catch (Exception e) { e.printStackTrace(); } } } Output results: Hello 9 a string Hello, Scripting
Javascript
Array object Create an array object: Format 1: Array object name=new Array([number of elements]) Format 2: Array object name = new Array([[Element 1][, Element 2,…]]) Format 3: Array object name = [Element 1[, Element 2,…]] Properties of array objects: Format: array object name.property Attribute: length Array length Methods of array objects: Format: array object name.method([parameter]) method: join([separator]) Combine array elements into strings toString() Represents an array as a string reverse() Array reverse valueOf() returns array value string object Create a string object: Format: String object name = new String (string constant) Format: string variable name=”string constant” Properties of string objects: Format: String object name. Properties Properties: length String length String object methods: Format: String object name.Method method: bold() bold italtics() italics strike() Strikethrough fontsize(font size) text size fontcolor(#rrggbb) text color sup() superscript sub() subscript toUpperCase() Uppercase toLowerCase() lowercase charAt(index) returns the character at the index position charCodeAt(index) Returns the ASCII character code of the index position, expressed in decimal format indexOf(“string”[,index]) Returns the index position of the string in the object lastIndexOf(“string”[,index]) Returns the index position of the string in the object (reverse search) search(“string”) Returns the index position of the string in the object replace(“String 1″,”String 2”) String 2 replaces…
Get second last record from firestoreDB, javascript
Since firestore is not very old, it can be of little help in some cases. I’m trying to get the second record from Firestore but it’s getting the first. I know this is the wrong query: db.collection(“batches”) .where(‘added_at’, “<", paymentData.added_at) //Here paymentData is last record .limit(1).get().then(function(prevSnapshot){ }) For example, I have 3 records A. added_at: 1 Jan, 2017 B. added_at: 2 Jan, 2017 C. added_at: 3 Jan, 2017 I now have C in paymentData and I want record B. But it is getting record A. How do I get the second last record? Edit: The timestamp of each record is always newer than the previous one (even though it can be 1 minute. For example, the previous 27 Jan, 2017 5:20 PM and the new one 27 Jan , 2017 5:21 PM) And paymentData will always have the latest record. Basically I want to compare two values Current payment and Previous payment and show the difference between it and the user. 1> Grimthorr..: The ordering of Firestore documents is not guaranteed unless you specifically order the documents in the query. To do this, you need to use the orderBy()Method. For example, you can specify that the database sorts documents by…
JavaScript,AJAX tree controls (allkindsofTreeViewControlsbyJavaScript,AJAX)
With Drag and Drop: 1 http: // www.bernardopadua.com / nestedSortables / test / nested_sortable / 2 http: // www.dhtmlgoodies.com / index.html?whichScript = drag – drop – folder – tree 3 http: // extjs.com / products / extjs / 4 http: // extjs.com / deploy / dev / examples / tree / reorder.html 5 http: // extjs.com / deploy / dev / examples / tree / two – trees.html 6 http: // www.telerik.com / community / forums / thread / b311D – gbcch.aspx 7 http: // www.codeproject.com / KB / tree / A_better_TreevIew_control.aspx 8 http: // www.codeproject.com / KB / asp / asptreeview.aspx Without Drag and Drop: 1, dTree 2, Treeview Javascript 3, YUI Tree Panel Component with drag and drop and more 4, Ajax drag’n drop folder tree by dhtmlgoodies.com[Example Page] 5、Update a tree with Ajax by dhtmlgoodies.com[Example Page] 6、Static list based folder Tree by dhtmlgoodies.com[Example Page] 7, Folder Tree (with PHP support)[Example Page] 8, Tree Control [Example Page ] 9, Expand/Collapse Panes 10, DHTML Tree 11、Nornix Tree Menu 12, Milonic Treemenu[Example Page] 13, jQuery treeView [animated] 14、Tigra Tree Menu 15、dhtmlxTree[Ajax powered with drag and drop function] 16, Yahoo UI Tree Controll 17, Dynamic Drive Simple Tree Menu 18, CheckTree…
Insert or similar content in form tags (HTML, JavaScript)
I have the following table: … form content… When the button is clicked, signup() calls a Javascript function. This function uses an AJAX call to validate the form (compared to the current database value) and then submits the form via a PHP function. My question is: If the user has disabled Javascript in their browser, is there a way to modify the tag to include actions and methods? Since HTML5 allows tags within the body, I thought I would try something like: action=”…” method=”post”> But this doesn’t work. I want the AJAX call to handle everything if the user has JS enabled – it makes for a very clean user experience. However, I need it to still work for those who have their JS disabled. Thank you in advance. 1> Christian Va..: You are looking at it the wrong way. You always want Include the action and method attributes in the form. You then bind a function to the submit event and prevent the form from being submitted by using .preventDefault(); (I assume jQuery is used here) $(‘#signup’).on(‘submit’, function(e) { e.preventDefault(); // submit data via ajax here }); This is much better because you don’t have to set the login…
Wu Yuxiong’s artificial intelligence java, javascript, HTML5, python, oracle – implementation of a concise version of the WEB side review code of the intelligent medical system
import sys import os import time importoperator import cx_Oracle import numpy as np import pandas as pd import tensorflow as tf conn=cx_Oracle.connect(‘doctor/admin@localhost:1521/tszr’) cursor = conn.cursor() def printHistory(userid): sql = “select username,sex,age,province,area,bumen,ke,result,chufang,jianyi,yiyuaan,yisheng,jianchaxiang,zhenduanriqi from zhenduanjilutable where userid= ‘%d'” % userid cursor.execute(sql) rows = cursor.fetchall() zhenduanjilu = [] for row in rows: temp = [] temp.append(row[0]) temp.append(row[1]) temp.append(row[2]) temp.append(row[3]) temp.append(row[4]) temp.append(row[5]) temp.append(row[6]) temp.append(row[7]) temp.append(row[8]) temp.append(row[9]) temp.append(row[10]) temp.append(row[11]) temp.append(row[12]) temp.append(row[13]) zhenduanjilu.append(temp) print(“====================Print diagnostic history=== ==================”) for i in range(len(zhenduanjilu)): print(“————–>>No.: ” +str(i+1)+”Diagnosis<<——————- “) print(” Name: “+zhenduanjilu[i][0]) print(” Gender: “+zhenduanjilu[i][1]) print(” Age: “+str(zhenduanjilu[i][2 ])) print(” Province: “+zhenduanjilu[i][3]) print(” Urban area: “+zhenduanjilu[i][4] ) print(” Outpatient department: “+zhenduanjilu[i][5] ) print(” Outpatient subjects: “+zhenduanjilu[i][6] ) print(” Diagnosis result: “+zhenduanjilu[i][7] ) print(” Medical prescription: “+zhenduanjilu[i][8] ) print(” Health advice: “+zhenduanjilu[i][9] ) print(” Recommended hospital: “+zhenduanjilu[i][10] ) print(” Recommended doctor: “+zhenduanjilu[i][11] ) print(” Suggested check items: “+zhenduanjilu[i][12 ]) print(” Diagnosis date: “+str(zhenduanjilu[i][13])) # printHistory(6) <%– Document: ALSelectHistory Created on : 2018-10-9, 21:28:13 Author: acer –%> <%@page import=”java.util.Iterator “%> <%@page import=”java.util.ArrayList “%> <%@page import=”java.util.List “%> <%@page import=”java.io.InputStreamReader “%> <%@page import=”java.io.Bpan >> <h2>Please enter the number of the follow-up record you need: <input type=”text” name=”hisid” value= “”/></h2> <input type=”hidden” name=”userid” value=””/> <input type=”hidden” name=”username” value=””/> <input type=”hidden” name=”province” value=””/> <input type=”hidden” name=”administr”…
javascript.,javascript study guide
What type of language is Javascript? javascrip Javascript is a literal scripting language. It is a dynamically typed, weakly typed, prototype-based language with built-in support for types. Its interpreter is called the Javascript engine, which is part of the browser and is widely used in client-side scripting languages. It was first used on HTML (an application under Standard Universal Markup Language) web pages to add dynamic functions to HTML web pages. . In 1995, it was first designed and implemented on the Netscape Navigator browser by Brendan Eich of Netscape. Because Netscape cooperated with Sun, Netscape management wanted it to look like Java, hence the name Javascript. But in fact its grammatical style is closer to Self and Scheme. In order to gain technical advantages, Microsoft launched JScript, and CEnvi launched ScriptEase, which can also run on the browser like Javascript. In order to unify the specifications, because Javascript is compatible with the ECMA standard, it is also called ECMAScript. Components ECMAScript describes the language’s syntax and basic objects. Document Object Model (DOM) describes the methods and interfaces for processing web content. Browser Object Model (BOM) describes the methods and interfaces for interacting with the browser. Basic features Javascript is…
JavaScript, calculate sum of all values in an array using for loop
I just started using Javascript a few weeks ago and am still struggling a bit. I need to create a loop that calculates the sum of all values from an array of votes in a separate .js file. This function has one parameter, vote, representing one of five voting arrays (vote1 to vote5). Add the following command to the function: A. Declare a variable named total and set its initial value to 0. Create a for loop that loops through each item in the votes array and adds the value of the item to the total variable. C. After completing the for loop, return the value of the total variable from the function. Here’s my html file. Nishi Gaba.. 7 You can use the reduce method of an array. The Reduce Method provides concatenated values based on the elements in the Array. For example: const sum = [1,2,3].reduce(function(result,item) { return result + item; }, 0); console.log(sum); The above code gives output 6 which is the sum of the given array. You can check other array methods on my Gist: Iterate_Over_Array.js 1> Nishi Gaba..: You can use the reduce method of an array. The Reduce Method provides concatenated values based on…
