How to get substring using Dojo and javascript - javascript

Good Day,
I am a newbie learning Javascript & Dojo and I typically learn by picking apart other parts of running code.
I am confused as to how to get a substring value from the following code (from the ArcGIS Sandbox):
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=7, IE=9, IE=10">
<!--The viewport meta tag is used to improve the presentation and behavior of the samples
on iOS devices-->
<meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no">
<title>Query State Info without Map</title>
<script src="http://js.arcgis.com/3.6/"></script>
<script>
dojo.require("esri.tasks.query");
dojo.require("esri.map");
var queryTask, query;
require([
"esri/tasks/query", "esri/tasks/QueryTask",
"dojo/dom", "dojo/on", "dojo/domReady!"
], function(
Query, QueryTask,
dom, on
){
queryTask = new QueryTask("http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer/5");
query = new Query();
query.returnGeometry = false;
query.outFields = ["SQMI","STATE_NAME","STATE_FIPS","SUB_REGION","STATE_ABBR","POP2000","POP2007","POP00_SQMI","POP07_SQMI","HOUSEHOLDS","MALES","FEMALES","WHITE","BLACK","AMERI_ES","ASIAN","OTHER","HISPANIC","AGE_UNDER5","AGE_5_17","AGE_18_21","AGE_22_29","AGE_30_39","AGE_40_49","AGE_50_64","AGE_65_UP"];
on(dom.byId("execute"), "click", execute);
function execute(stateName) {
query.text = dom.byId("stateName").value;
//execute query
queryTask.execute(query, showResults);
}
function showResults(results) {
var s = "";
for (var i=0, il=results.features.length; i<il; i++) {
var featureAttributes = results.features[i].attributes;
for (att in featureAttributes) {
s = s + "<b>" + att + ":</b> " + featureAttributes[att] + "<br>";
}
s = s + "<br>";
}
dom.byId("info").innerHTML = s;
}
});
</script>
</head>
<body>
US state name :
<input type="text" id="stateName" value="California">
<input id="execute" type="button" value="Get Details">
<br />
<br />
<div id="info" style="padding:5px; margin:5px; background-color:#eee;">
</div>
</body>
</html>
All I would like to do is pick apart the input (in this case the id="stateName" which is the word California).
So a silly example would be substituting the following code to get the first 10 characters of when someone types in 'California is on the west coast'
query.text = dom.byId("stateName").substring(0,10);
This is really so I can support other queries but I figured if I can do a substring on this input then it is really the same anytime when I query other attributes.
Thanks in advance for a newbie !

You need to get the innerHTML of your DOM element
query.text = dom.byId("stateName").value.substring(0, 10);

As Thomas Upton correctly pointed out the correct form would be:
dom.byId("stateName").value.substring(0, 10);
apparently the following also works
dom.byId("stateName").value.substr(0, 10);

As noted in comments, a call to .value will deliver what you need. Substring is a method on the string prototype See here. However, dom.byId returns a domNode. You don't want the substring of the domNode itself, you want the substring of the text value of the domNode. On inputs this is easily done with .value and is commonly done with .textContent and .innerHTML as well.

Related

Basic JavaScript how to call a function from the HTML page

I have just started JavaScript basics and I'm struggling with this:
HTML page has the following:
<body>
<p id="number">5</p>
<button id="buttonX" onclick="calcSquare()">Click here!</button>
</body>
This page should call the function calcSquare(), which fetches the value of the element, calculate its square, and print in the console: The square of 5 is 25. The HTML page loads the code, so I can refer to the page with the document keyword. My js code is following:
function calcSquare() {
var number = document.getElementById("number").value;
console.log("The square of" + number + "is" number*number);
}
Can someone tell me what is wrong with it? Thank you so much! Beginners struggles...
The problem is with your function itself.
Keep in mind that .value is used with an input element. So you can use .innerHTML or .textContent.
You forgot also the sign + after "is".
Look at this code snippet .
function calcSquare() {
var numbElementcontent = document.querySelector('#number').innerHTML;
numbElementcontent = parseInt(numbElementcontent);
console.log("The square of " + numbElementcontent + " is " + numbElementcontent * numbElementcontent);
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<p id="number">5</p>
<button id="buttonX" onclick="calcSquare()">Click here!</button>
<script>
function calcSquare() {
var numbElementcontent = document.querySelector('#number').innerHTML;
numbElementcontent = parseInt(numbElementcontent);
console.log("The square of " + numbElementcontent + " is " + numbElementcontent * numbElementcontent);
}
</script>
</body>
</html>
Instead of .value use .innerHTML, and you are missing sign + after "is"
You need to get textContent, and make some changes in your function calcSquare()
function calcSquare() {
var number = document.getElementById("number");
var number = number.textContent;
console.log("The square of" , number , "is" , number*number);
}
<body>
<p id="number">5</p>
<button id="buttonX" onclick="calcSquare()">Click here!</button>
</body>
And if you are use an input-field you make it more dynmaic :) and if the is target an input you can use the .value
Be sure you cast every time your vars into the right type before do math (parseInt, parseFloat etc)
And because you are new on JS please deal with JS Security - it is very important for your future dev..
https://snyk.io/learn/javascript-security/
https://glebbahmutov.com/blog/disable-inline-javascript-for-security/
Try this . Foe elements such as P or Div You have to ue textContent or innerHTML to get the data inside the tag. You missed string concatenation after "is" too
function calcSquare() {
var number = document.getElementById("number").textContent;
console.log("The square of" + number + "is" +number*number);
}
<body>
<p id="number">6</p>
<button id="buttonX" onclick="calcSquare()">Click here!</button>
</body>
<script>

Adding html table to javascript using document.write

Looking for some help here. Our class instructor is asking us to add a table into javascript using the document.write, I know this is not the recommended way to do this, but this is what our instructor is looking for:
Add code to the writeIt function that writes the opening table tag before iterating thru the heros and villians and then the closing table tag. Then modify the makeListItem to return a string in the form of tr td Hero td td Villan /td /tr.
I tried this but am getting a blank html page when try to view.
<!DOCTYPE html>
<html>
<head>
<title>JavaScript Functions</title>
<meta charset="utf-8" />
<script>
var superData = {"Super Man":["Lex Luther"],
"Bat Man":["Joker", "Riddler",],
"Spider Man":["Green Goblin",
"Vulture", "Carnage"],
"Thor":["Loki", "Frost Giants"]};
function writeIt('<table>'){
for (hero in superData){
var villains = superData[hero];
for (villainIdx in villains){
var villain = villains[villainIdx];
var listItem = makeListItem(<tr><td>Hero</td><td>Villan</td></tr>);
document.write(listItem);
}
}
}
function makeListItem(name, value){
var itemStr = "<li>" + name + ": " + value + "</li>";
return itemStr;
}
document.write('</table>');
</script>
</head>
<body onload="writeIt()">
</body>
</html>
Try this:
<!DOCTYPE html>
<html>
<head>
<title>JavaScript Functions</title>
<meta charset="utf-8" />
<script>
var superData = {
"Super Man": ["Lex Luther"],
"Bat Man": ["Joker", "Riddler", ],
"Spider Man": ["Green Goblin",
"Vulture", "Carnage"
],
"Thor": ["Loki", "Frost Giants"]
};
function writeIt() {
document.write('<table>');
for (hero in superData) {
document.write("<tr><td>" + hero + ": <ul>");
var villains = superData[hero];
for (villainIdx in villains) {
var villain = villains[villainIdx];
var listItem = makeListItem(villain);
document.write(listItem);
}
document.write("</ul></td></tr>");
}
}
function makeListItem(value) {
var itemStr = "<li>" + value + "</li>";
return itemStr;
}
document.write('</table>');
</script>
</head>
<body onload="writeIt()">
</body>
</html>
I tried this but am getting a blank html page when try to view.
Because you have syntax problems. Use F12 or the Inspector/Developer mode to find out why.
Our class instructor is asking us to add a table into javascript using the document.write, I know this is not the recommended way to do this, but this is what our instructor is looking for
True, it's often frowned upon, but JavaScript makes it available for a reason, so let's use it.
The first problem is that you seem to have transposed some code...
For example, you have function writeIt('<table>'). I think you meant document.write('<table>');.
function writeIt(){
document.write('<table>');
Next, you have your final document.write outside of your function call.
document.write('</table>');
This should be inside writeIt(), just after your for loop.
Finally, you have some unquoted stuff in your loop...
makeListItem(<tr><td>Hero</td><td>Villan</td></tr>);
Should be (single or double quotes):
makeListItem('<tr><td>Hero</td><td>Villan</td></tr>');
But that's still a bit off for a table. For example, Superman has a 1:1 ratio with his villains and Batman has a 1:2 ratio. You should be adding your rows and tables in a more predictable manner, but the above will at least start to give you output to work from.
Finally, an observation is that your makeListItem needs to use <ul> before it uses <li> so those problems need to be resolved. For now, I recommend you just spit the data out and format it later.

jQuery returned data isn't tidy

I'm new to using JavaScript so please excuse my bad terminology.
I have a jQuery that is calling an API for a dictionary web service, the whole function works as it should (returning all of the definitions, authors, etc..).
But my problem is that the returned data from the API is coming back in one big block of text and not in a neat format with line spacing between each definition.
If I just search for the URL in a web browser, I get a json response with tidy definitions and spacing.
Here is my search in the service to the API and the data returned.
http://epvpimg.com/MkdEg
Here is the search just using the URL from my code through a web browser (how I think it should look when returned in my web service)
http://epvpimg.com/IWLJf
Has anybody ever seen this problem before or know why, from my code, it is doing so!
Any help would be much appreciated!
$(document).ready(function(){
$('#term').focus(function(){
var full = $("#definition").has("definition").length ? true : false;
if(full === false){
$('#definition').empty();
}
});
var getDefinition = function(){
var word = $('#term').val();
if(word === ''){
$('#definition').html("<h2 class='loading'>We haven't forgotten to validate the form! Please enter a word.</h2>");
}
else {
$('#definition').html("<h2 class='loading'>Your definition is on its way!</h2>");
$.getJSON("http://glosbe.com/gapi/translate?from=eng&dest=eng&format=json&phrase=&pretty=true" +word+ "?callback=?", function(json) {
if (json !== "No definition has been found."){
var reply = JSON.stringify(json,null,"\t");
var n = reply.indexOf("meanings");
var sub = reply.substring(n+8,reply.length);
var subn = sub.indexOf("]");
sub = sub.substring(0,subn);
$('#definition').html('<h2 class="loading">We found you a definition!</h2><h3>'+sub+'</h3>');
}
else {
$.getJSON("http://glosbe.com/gapi/translate?from=eng&dest=eng&format=json&phrase=&pretty=true" + "?callback=?", function(json) {
console.log(json);
$('#definition').html('<h2 class="loading">Nothing found.</h2><img id="thedefinition" src=' + json.definition[0].image.url + ' />');
});
}
});
}
return false;
};
$('#search').click(getDefinition);
$('#term').keyup(function(event){
if(event.keyCode === 13){
getDefinition();
}
});
});
And the HTML
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="author" content="Matthew Hughes">
<meta name="Dictionary" content="A dictionary web service">
<title>Dictionary Web Application</title>
<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.6.2.min.js"></script>
<script src="dictionary.js"></script>
<link rel="stylesheet" href="style.css" />
</head>
<body>
<div id="container">
<div id="top">
<header>
<h1>Dictionary Application</h1>
</header>
</div>
<div id="app">
<input type="text" placeholder="Enter a word..." id="term" />
<button id="search">Define!</button>
<section id="definition">
</section>
</div>
<footer>
<p>Created by Matthew Hughes</p>
</footer>
</div>
</body>
You're providing a third argument to JSON.stringify, which pretty-prints the result. So sub should have the line breaks you want. The problem is that you're putting it in an HTML document, and HTML automatically merges lines. You can prevent this by using the <pre> tag:
$('#definition').html('<h2 class="loading">We found you a definition!</h2><br><pre>'+sub+'</pre>');

Concatenate Strings in JavaScript

I Have edited the code, the updated code is below, This code is not able to fetch the keywords meta tag, hence it is not working.
old description: I am trying to concatinate the strings to get the finalUrl, but I am not able to do so becuase of the tags variable. I need to fetch the keywords meta tag of the page and append it to get the finalUrl. Any help?
<script type="text/javascript">
var tags=$('meta[name=keywords]').attr("content");
var gameurl = "http://xyz/abc/details/";
var jsn = ".json?callback=showGameDetail";
var finalUrl= gameurl.concat(tags).concat(jsn);
function loadJSON(url) {
var headID = document.getElementsByTagName("head")[0];
var newScript = document.createElement('script');
newScript.type = 'text/javascript';
newScript.src = url;
headID.appendChild(newScript);
}
function showGameDetail(feed){
var title = feed.title;
var game_url = feed.pscomurl;
var packart_url = feed.Packart;
$("#bnr-ads-box").html("<img src='"+"http://abc.com/"+packart_url+"'>");
}
loadJSON(finalUrl);
</script>
<div id="bnr-ads-box"></div>
<!DOCTYPE html>
<html>
<head>
<meta id="metaK" name="keywords" content="customizable software for QuickBooks, QuickBooks-integrated, Method customization, CRM accounting, Method for QuickBooks, Method CRM, Method blog, Salesforce automation, Method online platform, QuickBooks customization, web-based platform, industry-specific, customer portal, Method Field Services, Method Manufacturing, ERP" />
<script type="text/javascript" src="http://code.jquery.com/jquery-1.10.2.min.js"></script>
</head>
<body>
<p id="demo">Click the button to join two strings into one new string.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction()
{
var tags=$('meta[name=keywords]').attr("content");
var gameurl = "http://xyz/abc/names/";
var jsn = ".json?callback=showGameDetail";
var finalUrl= gameurl.concat(tags).concat(jsn);
document.getElementById("demo").innerHTML=finalUrl;
}
</script>
</body>
</html>
change this
var tags="$('meta[name=keywords]').attr("content");";
to
var tags=$('meta[name=keywords]').attr("content");
also use this code var finalUrl = gameurl + tags + jsn;
What you need is to escape the double quotes inside your tags variable, like so:
var tags="$('meta[name=keywords]').attr(\"content\");";
Cris' solution is also fine, but in some case you will need to have two sets of double quotes inside a string so you will be forced to do escaping correctly.
FYI: Escaping is the process of having special characters getting generated in a string which would otherwise cause issues, for instance in javascript you can't have newlines in a string, like this:
var mystring = 'on
a different line'; // <- this causes a syntax error
So one would do the following:
var mystring = 'on\na different line';
You forgot to include the jquery
<!DOCTYPE html>
<html>
<head>
<meta name="keywords" content="hello"/>
<script type="text/javascript" src="http://code.jquery.com/jquery-1.10.2.min.js"></script>
<script type="text/javascript">
function myFunction()
{
alert("Hello World!");
var tags=$('meta[name=keywords]').attr("content");
var gameurl = "http://xyz/abc/names/";
var jsn = ".json?callback=showGameDetail";
var finalUrl= gameurl.concat(tags).concat(jsn);
alert(finalUrl);
}
</script>
</head>
<body>
<button onclick="myFunction()">Try it</button>
</body>
</html>
Tough debatable, you can use an array, which can be concatenated by calling join():
var tags = $('meta[name=keywords]').attr("content");
var data = [
"http://xyz/abc/names/",
encodeURIComponent(tags),
".json?callback=showGameDetail"
].join('');
$("#demo").html(data);
Actually the concat method works on strings too (in chrome at least) but the recommended method is using the plus concatenation string operator
You are however missing some stuff
jQuery library - I assume you want that since you have $(...) in the example
encoding of the string from the keywords - I use encodeURIComponent to handle possible newlines and quotes in the keywords
.
<!DOCTYPE html>
<html>
<head>
<title>Create a URL from keywords</title>
<meta name="keywords" content="These are tags" />
<script src="http://code.jquery.com/jquery-1.10.2.min.js"></script>
<script>
function myFunction() {
var tags = $('meta[name=keywords]').attr("content");
var URL ="http://xyz/abc/names/" +
encodeURIComponent(tags) +
".json?callback=showGameDetail";
window.console && console.log(URL);
$("#demo").html(URL);
}
</script>
<body>
<p id="demo">Click the button to join two strings into one new string.</p>
<button onclick="myFunction()">Try it</button>
</body>
</html>

Returning currently displayed index of an array Javascript

I have a simple array with x number of items. I am displaying them individually via a link click... I want to update a number that say 1 of 10. when the next one is displayed i want it to display 2 of 10 etc...
I have looked all around and my brain is fried right now... I know its simple I just cant get it out.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title>Page Title</title>
<link rel="stylesheet" href="style.css" type="text/css" media="screen" charset="utf-8"/>
<script type="text/javascript">
var quotations = new Array()
quotations[0]= "abcd"
quotations[1]= "efgh"
quotations[2]= "ijkl"
quotations[3]= "mnop"
quotations[4]= "qrst"
quotations[5]= "uvwx"
quotations[6]= "yzab"
numQuotes = quotations.length;
curQuote = 1;
function move( xflip ) {
curQuote = curQuote + xflip;
if (curQuote > numQuotes)
{ curQuote = 1 ; }
if (curQuote == 0)
{ curQuote = numQuotes ; }
document.getElementById('quotation').innerHTML=quotations[curQuote - 1];
}
var curPage = curQuote
</script>
</head>
<body>
<div id="quotation">
<script type="text/javascript">document.write(quotations[0]);</script>
</div>
<div>
<p>GO back
<script type="text/javascript">document.write(curPage + " of " + numQuotes)</script>
GO FORTH</p>
</div>
</body>
</html>
Edit: curQuote is not updating dynamically... it stays at '1' when next is clicked.
In your code, curQuote is already the value you want. I rewrote everything to clean it up and show some better logic/syntax. Note that ideally you would be attaching the click handlers via DOM methods and not using inline handlers, but for simplicity I've left it that way here.
Working version viewable here: http://jsbin.com/irihu3/2
<html>
<head>
<title>Quotations</title>
<script type="text/javascript" charset="utf-8">
var quotations = ["hi", "how", "are", "you", "today", "good", "sir"],
lastIndex = quotations.length - 1,
currentIndex = 0;
function move(xflip) {
currentIndex = currentIndex + xflip;
if (currentIndex > lastIndex) {
currentIndex = 0;
} else if (currentIndex < 0) {
currentIndex = lastIndex;
}
document.getElementById('quotation').innerHTML = quotations[currentIndex] + " (Quote #" + (currentIndex + 1) + ")";
return false;
}
</script>
</head>
<body>
<div id="quotation">hi (Quote #1)</div>
<a onclick="move(-1);">Prev</a>
<a onclick="move(1)">Next</a>
</body>
</html>
Some things to note:
Always declare variables with the var keyword or you create global variables.
You can combine multiple variable declarations into one statement by separating them with commas. It's good practice to stick to one var statement and to put it at the top of your code/function.
All you really need to keep track of here is the current index of the array, not the quote itself. It's also not important how long the array is, just what the last index is. As such, in my code I am using currentIndex and lastIndex instead of curQuote and numQuotes.
Using return false; at the end of your function will suppress the default action when clicking on a hyperlink (not following the link). This is what you want in this case, because you're using a hyperlink to trigger behavior on the page and not actually navigating to another page.
You're making a lot of beginner mistakes in your JavaScript but it seems as if curQuote has the value you want, no?
Tips:
You can declare an array as such: var array = [1,2,3,4,5,6,7];
Terminate statements with a semi-colon.
Use var keyword for local variables.
Don't put braces around one line if statements bodies.
Use indentation properly to make the code readable.
Try this
var curPage = quotations[curQuote];

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