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iframes - Child to Parent Communication

Problem: I wanted to embed a form into an webpage.  Easy enough!  As I tested the form in the iframe, I noticed the form height would change during validation. As error messages pop up, the form height would increase, and before I knew it, half the form was hidden in the iframe.  I needed to figure out a way to adjust the iframe according to the content height in the iframe . Solution: I discovered a way for an iframe and it’s parent to communicate.  In the iframe content (child), I figured out a way to post a message (body height) to the parent. When an error occured, I would run this code: let body = document.getElementsByTagName('body')[0]; parent.postMessage('formHeight', body.offsetHeight); In the parent page, I set up an event handler to always be listening for a message from the child.  When the parent detects a message, I can receive and use the data for whatever I want.  In my case, change the height of the iframe: ...
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Basic Recursion Example in JavaScript

Problem :  I've been having to write solutions which required some sort of recursion.  The last recursion assignment I had to write was a homework assignment about 10 years ago. I remembered the concept, but forgot how to write it. Solution :  Here’s a simple example of recursion. I start with an array, and after I fire the function, I remove that index from the array, so it shrinks. Once the array is empty, recursion stops.  Pretty straight forward! Code : let books = [ 'Chosen by God', 'Holiness of God', 'Essential Truths', 'Justified by Faith' ]; function readBooks(b){ while (b.length > 0){ console.log('I\'v read ' + b[0]); b.shift(); readBooks(b); } } readBooks(books);
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ArcGIS Javascript API - Pinpoint a Geo-Location by Address

Problem: I needed a map embedded on a form I was working on to pinpoint a location onto an ArcGIS map.  As far as ArcGIS, there were plenty of examples using latitude and longitude, but no examples using a standard address. This project seemed easier than it really was. Solution: I’ve decided to use the Javasript API to solve this problem and it worked like a charm.  Those who are new to ArcGIS should find this post helpful if you want to simply point to a location using an address.  Let’s get right to the code. Code: This is just very basic markup to show what files to include and what form elements to use. HTML (index.html): <html> <head>     <link rel="stylesheet" href="https://js.arcgis.com/3.18/esri/css/esri.css">     <style>         html, body, #myMap {             height: 400px;  ...
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