I have a confusing problem where a line of code in my function is running before a loop which is stated above it. In my HTML I have:
<textarea id="textBox"></textarea>
<button id="submitButton" onclick="parseData()">submit</button>
<div id="put"></div>
And my JS function is:
function parseData() {
var data = $("#textBox").val();
var tab = /\t/;
data = data.split(tab);
$("#put").html($("#put").html() + "<table>");
for (var i = 0; i < data.length; i++) {
$("#put").html($("#put").html() + "<tr>"+data[i]+"</tr>");
};
$("#put").html($("#put").html() + "</table>");
return;
};
The resulting html in $("#put") is this:
<table></table>
"SiO2 (%)Al2O3 (%)TiO2 (%)CaO2 (%)MgO2 (%) 8.21.25.31.51.8 45.32.52.60.210.5 65.23.48.70.0662.3 20.11.85.42.540.2 18.91.12.34.810.7"
I'm not sure why the final </table> is being placed before the for loop runs, and I'm not sure why the <tr> tags aren't being added within the for loop. Any pointers?
jQuery automatically closes up tags upon insertion. Try this.
function parseData() {
var data = $("#textBox").val();
var tab = /\t/;
var put_html = $("#put").html() + "<table>";
data = data.split(tab);
for (var i = 0; i < data.length; i++) {
put_html += "<tr>"+data[i]+"</tr>";
};
put_html += '</table>';
$("#put").html(put_html);
return;
};
However, I notice that you aren't using <td> elements. You might want to look into fixing that too.
Every time you are adding content into the html() property rather than building the entire content and adding it.
Since you are using jQuery you can bind the event using jQuery rather than adding that directly in the HTML
<textarea id="textBox"></textarea>
<button id="submitButton">submit</button>
<div id="put"></div>
$(function(){
$("#submitButton").click(function(){
parseData();
});
function parseData() {
var data = $("#textBox").val();
var tab = /\t/;
data = data.split(tab);
// Build your html
$("#put").html('htmlstructure');
return;
}
});
Also you can look for something similar like concatenating the string in an array so that you don't create string isntances each time when you append, since strings are immutable.
Good example
Related
I have a form that has multiple fields all with the same class. These are populated with URL's that follow the same structure. I am trying to extract the same section from each URL. So far var res = x.split('/')[5]; will achieve this but only for the first URL. I can also use var x = document.querySelectorAll(".example") to change all the url's but I cannot find the correct way to combine both of these function. so far my code looks like this:
script>
function myFunction() {
var x = document.querySelectorAll(".example").innerHTML;
var res = x.split('/')[5];
var i;
for (i = 0; i < x.length; i++) {
x[i].innerHTML = res;
}
}
</script>
I have looked around but can't find a solution that fits. Thanks in advance for your help.
So loop over the HTML Collection, this is making assumptions based on code.
// Find all the elements
var elems = document.querySelectorAll(".example")
// loop over the collection
elems.forEach(function (elem) {
// reference the text of the element and split it
var txt = elem.innerHTML.split("/")[5]
// replace the text
elem.innerHTML = txt
})
<div class="example">1/2/3/4/5/a</div>
<div class="example">1/2/3/4/5/b</div>
<div class="example">1/2/3/4/5/c</div>
<div class="example">1/2/3/4/5/d</div>
<div class="example">1/2/3/4/5/e</div>
<div class="example">1/2/3/4/5/f</div>
I wanted to make a javascript loop in html like the following:
( if (var i=0; i<10; i++) { ) //<-- JAVASCRIPT
//HTML
( } ) //<-- JAVASCRIPT
I tried using the <% JAVASCRIPT %> but it won't work for me. Does anyone know who to solve this?
Thanks in advance.
This is not how javascript works. This is something you would do with PHP.
With javascript, you run it seperately from the html. Then, you create an element within your html as a wrapper to put the javascript generated html into. Like so:
HTML
<div id="myHTMLWrapper">
</div>
<script>
var wrapper = document.getElementById("myHTMLWrapper");
var myHTML = '<span class="test">Testing out my script!</span>';
wrapper.innerHTML = myHTML
</script>
See a working example here
Sorry I skipped over the for loop by the way. Let me fix it with this update... You could do it like this, you see:
<script>
var wrapper = document.getElementById("myHTMLWrapper");
var myHTML = '';
for (var i = 0; i < 10; i++) {
myHTML += '<span class="test">Testing out my script! loop #' + (i + 1) + '</span><br/><br/>';
}
wrapper.innerHTML = myHTML
</script>
for loops are control flow and thus cannot be inserted into a static context. Try mapping it, e.g.
`<html>` + data.map(function(a) { return `<div>${a}</div>` }).join('') + `</html>`
<script>
for(var i=0; i<10; i++) {
//Code here
}
</script>
https://www.w3schools.com/js/js_if_else.asp
https://www.w3schools.com/js/js_loop_for.asp
I'd suggest you read a bit before going straight into coding
Either way your script seems deficient and I cant make out what you are trying to do with it.
Check these links if you want to append elements:
https://www.w3schools.com/jquery/html_append.asp
https://www.w3schools.com/jsref/met_node_appendchild.asp
I apologize in advance, this is the first Stack Overflow question I've posted. I was tasked with creating a new ADA compliant website for my school district's technology helpdesk. I started with minimal knowledge of HTML and have been teaching myself through w3cschools. So here's my ordeal:
I need to create a page for all of our pdf and html guides. I'm trying to create a somewhat interactable menu that is very simple and will populate a link array from an onclick event, but the title="" text attribute drops everything after the first space and I've unsuccessfully tried using a replace() method since it's coming from an array and not static text.
I know I'm probably supposed to use an example, but my work day is coming to a close soon and I wanted to get this posted so I just copied a bit of my actual code.
So here's what's happening, in example 1 of var gmaildocAlt the tooltip will drop everything after Google, but will show the entire string properly with example 2. I was hoping to create a form input for the other helpdesk personnel to add links without knowing how to code, but was unable to resolve the issue of example 1 with a
var fix = gmaildocAlt.replace(/ /g, "&nb sp;")
//minus the space
//this also happens to break the entire function if I set it below the rest of the other variables
I'm sure there are a vast number of things I'm doing wrong, but I would really appreciate the smallest tip to make my tooltip display properly without requiring a replace method.
// GMAIL----------------------------
function gmailArray() {
var gmaildocLink = ['link1', 'link2'];
var gmaildocTitle = ["title1", "title2"];
var gmaildocAlt = ["Google Cheat Sheet For Gmail", "Google 10-Minute Training For Gmail"];
var gmailvidLink = [];
var gmailvidTitle = [];
var gmailvidAlt = [];
if (document.getElementById("gmailList").innerHTML == "") {
for (i = 0; i < gmaildocTitle.length; i++) {
arrayGmail = "" + gmaildocTitle[i] + "" + "<br>";
document.getElementById("gmailList").innerHTML += arrayGmail;
}
for (i = 0; i < gmailvidTitle.length; i++) {
arrayGmail1 = "";
document.getElementById("").innerHTML += arrayGmail1;
}
} else {
document.getElementById("gmailList").innerHTML = "";
}
}
<div class="fixed1">
<p id="gmail" onclick="gmailArray()" class="gl">Gmail</p>
<ul id="gmailList"></ul>
<p id="calendar" onclick="calendarArray()" class="gl">Calendar</p>
<ul id="calendarList"></ul>
</div>
Building HTML manually with strings can cause issues like this. It's better to build them one step at a time, and let the framework handle quoting and special characters - if you're using jQuery, it could be:
var $link = jQuery("<a></a>")
.attr("href", gmaildocLink[i])
.attr("title", gmaildocAlt[i])
.html(gmaildocTitle[i]);
jQuery("#gmailList").append($link).append("<br>");
Without jQuery, something like:
var link = document.createElement("a");
link.setAttribute("href", gmaildocLink[i]);
link.setAttribute("title", gmaildocAlt[i]);
link.innerHTML = gmaildocTitle[i];
document.getElementById("gmailList").innerHTML += link.outerHTML + "<br>";
If it matters to your audience, setAttribute doesn't work in IE7, and you have to access the attributes as properties of the element: link.href = "something";.
If you add ' to either side of the variable strings then it will ensure that the whole value is read as a single string. Initially, it was assuming that the space was exiting the Title attribute.
Hope the below helps!
UPDATE: If you're worried about using apostrophes in the title strings, you can use " by escaping them using a . This forces JS to read it as a character and not as part of the code structure. See the example below.
Thanks for pointing this one out guys! Sloppy code on my part.
// GMAIL----------------------------
function gmailArray() {
var gmaildocLink = ['link1', 'link2'];
var gmaildocTitle = ["title1", "title2"];
var gmaildocAlt = ["Google's Cheat Sheet For Gmail", "Google 10-Minute Training For Gmail"];
var gmailvidLink = [];
var gmailvidTitle = [];
var gmailvidAlt = [];
if (document.getElementById("gmailList").innerHTML == "") {
for (i = 0; i < gmaildocTitle.length; i++) {
var arrayGmail = "" + gmaildocTitle[i] + "" + "<br>";
document.getElementById("gmailList").innerHTML += arrayGmail;
}
for (var i = 0; i < gmailvidTitle.length; i++) {
var arrayGmail1 = "";
document.getElementById("").innerHTML += arrayGmail1;
}
} else {
document.getElementById("gmailList").innerHTML = "";
}
}
<div class="fixed1">
<p id="gmail" onclick="gmailArray()" class="gl">Gmail</p>
<ul id="gmailList"></ul>
<p id="calendar" onclick="calendarArray()" class="gl">Calendar</p>
<ul id="calendarList"></ul>
</div>
I'm developing a program which basically just receives input from the user twice (risk carrier and sum, but that's just a placeholder to make my program less abstract), groups those two values together and then repeats the contents in a loop. See the code below.
<head>
<script type="text/javascript">
function fillArray(){
document.getElementById("danke").innerHTML = "Thanks for specifying the amount of entries.";
var numberOfEntries = parseInt(document.getElementById('input0').value);
var i = 0;
var myArrA = [];
var myArrB = [];
var x = " ";
while(i<numberOfEntries){
var neuRT = prompt("Enter a risk carrier");
myArrA.push(neuRT);
var neuRH = prompt("Enter a risk sum");
myArrB.push(neuRH);
i++;
}
for(i = 0; i<anzahlEintraege; i++){
x = myArrA[i] + " carries a risk of " + myArrB[i];
document.getElementById("test").innerHTML = x;
}
}
</script>
</head>
<body>
<h1>risk assessment</h1>
<input type="text" id="input0" />
<button type="button" onclick="fillArray()">Number of entries</button> <p id="danke"></p>
<button type="button" onclick="untilNow()">Show all entries so far</button>
<br />
<br />
<div id="test"></div>
</body>
</html>
My issues are:
1.) I want to display the array by writing into an HTML element, which I attempted in the for-loop. Pop-ups are to be avoided. How can I loop through HTML elements, such as demo1, demo2, demo3 etc.? I can't just write <p id="demo" + i></p>. What other options are there?
2.) Say I want to make use of the untilNow() function. The scope of my arrays is limited to fillArray(). Do I need to "return" the arrays to the untilNow() function as parameters?
Thanks everyone!!!
The problem with your current code is that you're replacing the html by the last value in every loop. You're using = rather than +=. So, a quick fix would be to replace:
document.getElementById("test").innerHTML = x;
by:
document.getElementById("test").innerHTML += x;
An example of how you could wrap an array of strings in HTMLElements and add them to your document (note that there are many other ways/libraries to achieve the same result):
var myStrings = ["Hello", "stack", "overflow"];
// Two performance rules:
// 1. Use a fragment to prevent multiple updates to the DOM
// 2. No DOM queries in the loop
var newContent = myStrings.reduce(function(result, str) {
var li = document.createElement("li");
var txt = document.createTextNode(str);
li.appendChild(txt);
result.appendChild(li);
return result;
}, document.createDocumentFragment());
// Actually add the new content
document.querySelector("ul").appendChild(newContent);
<ul class="js-list"></ul>
I'm working on a personal project and I've run into an issue that I haven't been able to solve.
Here is a function that generates new table rows into a table (with id of "tableData") when a button is clicked:
function addNewRow(){
var tableEl = document.getElementById("tableData");
var newLine = '<tr class="newEntry">';
var classArray = ["classA", "classB", "classC", "classD"];
for (var i = 0; i < classArray.length; i++){
newLine += '<td><input class="' + classArray[i] + '"></td>';
}
newLine += '</tr>';
tableEl.insertAdjacentHTML("beforeend", newLine);
}
document.getElementById("addRow").addEventListener("click", addNewRow, false);
//the element with id="addRow" is a button
I've simplified the code for the above function for the sake of readability as it's not the focus of the problem. When the button is clicked, a new row is added successfully.
The problematic part involves another function that takes the sum of the respective classes of each row and displays them in a div.
The goal is to get the sum of the values of all input fields with matching class names. For example, let's say I use the addNewRow function to get six rows. Then I want to have the div showing the sum of the values of all input fields with the class name of "classA"; the number in that div should be the sum of those six values, which gets updated as I type in the values or change the existing values in any of the input fields with class name of "ClassA".
function sumValues(divId, inputClass){
var sumVal = document.getElementsByClassName(inputClass);
var addedUp = 0;
for (var j = 0; j < sumVal.length; j++){
addedUp += Number(sumVal[j].value);
}
document.getElementById(divId).innerHTML = addedUp;
}
Here are a couple (out of several) failed attempts:
document.input.addEventListener("keyup", sumValues("genericDivId", "classA"), false);
document.getElementsByClassName("classA").onkeyup = function(){sumValues("genericDivId", "classA");}
Unfortunately, after scouring the web for a solution and failing to find one, I just added an event listener to a button that, when clicked, would update the div to show the sum of values. Also had to modify the sumValues function to take values from an array rather than accepting arguments.
My question is: How can I modify the code so that the sum value updates as I type in new values or change existing values using pure Javascript (vanilla JS)?
You are very close, document.getElementsByClassName() returns an array of DOM objects, you need to set the onkeyup function for each and every element by looping through that array.
var classA = document.getElementsByClassName('classA'); // this is an array
classA.forEach(function(elem){ // loop through the array
elem.onkeyup = function(){ // elem is a single element
sumValues("genericDivId", "classA");
}
}
Hopefully this fixes your issue
Maybe the example below is not same with your situation, but you'll get the logic, easily. Anyway, do not hesitate to ask for more guide.
document.getElementById("row_adder").addEventListener("click", function() {
var t = document.getElementById("my_table");
var r = t.insertRow(-1); // adds rows to bottom - change it to 0 for top
var c = r.insertCell(0);
c.innerHTML = "<input class='not_important_with_that_way' type='number' value='0' onchange='calculate_sum()'></input>";
});
function calculate_sum() {
var sum = ([].slice.call(document.querySelectorAll("[type=number]"))).map(e=>parseFloat(e.value)).reduce((a, b) => a+b);
document.getElementById("sum").innerHTML = sum;
}
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<div>
<p>
<strong>Sum</strong>:<span id="sum">0</span>
</p>
</div>
<button id="row_adder">
Click me
</button>
<table id="my_table">
</table>
</body>
</html>