Can I assign a form to a variable? - javascript

So if I have a form called myForm and a field called myField, I know I can access that field by using:
document.myForm.myField.value
Is there a way to assign the form itself to a variable like:
var f = document.myForm
so that I can access the fields by just using:
f.myField.value in order to save myself some typing?
I tried it and it didn't work so I don't know if it's not possible or if I'm just doing something wrong.

Yes.
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>JS Bin</title>
</head>
<body>
<form id="example">
<input name="field" value="default value">
</form>
<script>
var frm = document.forms.example;
alert(frm.elements.field.value);
</script>
</body>
</html>

Yeah of course you can do it! Just add a variable like var act_form = document.forms["myform"]; //make use of it
var action =act_form.action, method = act_form.method;
alert(method);
and in the form contains
<form name="myform" method="post" action="example.com"></form>

Related

how to auto detect the current form element with same class name

Iam appending a form from desktop view and adding it to mobile view (including scripts) using append() . Since Iam appending same class name and ID for form elements., on submitting form., it is identifying the mobile layout form and passing empty value on trying to get value using document.getElementsByClassName('txtbox').value.
As per my requirement., I need to give index to identify each form while appending. like document.getElementsByClassName('txtbox')[0].value. I have done an approach for same. But not getting how to increment index value on appneding. I have created plunker for same. Please let me know what I have missed.
Here is the sample code
$(document).ready(function(){
var data = $(".div1").html();
$(".div2").append(data);
$("form").submit(function(){
console.log(document.getElementsByClassName('txtbox').value);
/*console.log(document.getElementsByClassName('txtbox')[0].value);
console.log(document.getElementsByClassName('txtbox')[1].value) ; */
});
});
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="style.css">
<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
<script src="script.js"></script>
</head>
<body>
<div class="div1">
// data to be copied
<form class="search-container" onsubmit="event.preventDefault();window.open(abc/cde/+'?q='+document.getElementsByClassName('txtbox').value),'_self');">
<input type="text" class="txtbox" id="txtbox" placeholder="enter here...">
<input type="submit" name="submit" /></form>
</div>
<div class="div2">
//data to be appended
</div>
</body>
</html>
You may use $(this).find() to select .txtbox inside the form.
$("form").submit(function() {
console.log($(this).find('.txtbox').val());
return false; // for debugging
});
Also, please note that id should be unique in the documnt.
I have passed form object inside function call and used that param to identify current form.
$(document).ready(function(){
var data = $(".div1").html();
$(".div2").append(data);
});
function submitForm(form){
var txtValue = $(form).find('.txtbox').val();
console.log(txtValue);
}
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="style.css">
<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
<script src="script.js"></script>
</head>
<body>
<div class="div1">
// data to be copied
<form class="search-container" onsubmit="event.preventDefault();submitForm(this);">
<input type="text" class="txtbox" id="txtbox" placeholder="enter here...">
<input type="submit" name="submit" /></form>
</div>
<div class="div2">
//data to be appended
</div>
</body>
</html>
You can iterate through you class list like so:
var txtboxes = document.getElementsByClassName("txtbox");
for(var i = 0; i < txtboxes.length; i++){
// ... process each element here
$(txtboxes[i]).append(data);
}

Javascript Input Paste registers as Undefined

I am currently writing a function that writes a bit of code for me based on an input. I am currently working on creating the input and the code that pastes the input, but whenever it writes, it shows up as undefined. This is the code.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Javascript YAML Generator</title>
</head>
<body>
<form class="yamlform" action="index.html" method="post">
<input type="text" name="appname" value="Name">
<button type="submit" onclick="writeAppName()">Submit</button>
</form>
<script type="text/javascript">
var appname = document.getElementsByName("appname").value
function writeAppName() {
document.write(appname)
}
</script>
</body>
</html>
NOTE: This is not my final version of the code, at the moment I just want a system for writing an input value that I can duplicate. Final version will be using document.getElementbyID.
document.getElementsByName returns colection. Use document.getElementsByName("appname")[0].value.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Javascript YAML Generator</title>
</head>
<body>
<form class="yamlform" action="index.html" method="post">
<input type="text" name="appname" value="Name">
<button type="submit" onclick="writeAppName()">Submit</button>
</form>
<script type="text/javascript">
var appname = document.getElementsByName("appname")[0].value
function writeAppName() {
document.write(appname)
}
</script>
</body>
</html>
You need to refer to the first element with name "appname", because it could be a collection. Also I but the assignment for appanme variable inside of the function, this will make it so appname isn't being assigned to "Name" right away and is instead assigned to whatever is in the text box when you click the botton
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Javascript YAML Generator</title>
</head>
<body>
<form class="yamlform" action="index.html" method="post">
<input type="text" name="appname" value="Name">
<button type="submit" onclick="writeAppName()">Submit</button>
</form>
<script type="text/javascript">
function writeAppName() {
var appname = document.getElementsByName("appname")[0].value
document.write(appname)
}
</script>
</body>
</html>
The problem is with your document.getElementsByName
It is possible that multiple elements would have same name.
While using document.getElementsByName, there might be multiple elements instead of a single element present in DOM with similar name, so document.getElementsByName returns an array (a list of elements) and not a single element
To use different elements of the Array, use
document.getElementsByName("appname")[0] // For first element with name
document.getElementsByName("appname")[1] // For second element with name
// and so on
So in your code, you would use
var appname = document.getElementsByName("appname")[0].value;

Can't receive value from input field

i have problem on sending textbox value from one html page to another html page.
In first page i am sending first name and last name values.and i want to catch this value in textbox on the second page( i.e home.html).but some erroe occurs.
error is :Uncaught TypeError: Cannot set property 'value' of null
how to solve? please tell me.
i know this stupid question.but please tell me guys.i don't know javascript.
this is my html code:
<!DOCTYPE html">
<html>
<head>
<script src="ttt.js"></script>
</head>
<body>
<form method="get" action="home.html" name="ff">
Firstname: <input id="f" type="text" name="firstname1">
Lastname: <input type="text" name="lastname">
<input type="submit">
</form>
</body>
</html>
this is my home.html code:
<!DOCTYPE html">
<html>
<head>
<script src="ttt.js"></script>
<script Language="JavaScript">
var tttt=val();
document.getElementById('text').value=tttt;
</script>
</head>
<body>
<form name="ff">
<input id="text" class="text" type="text" name="MyValue" value="helloS"/>
</form>
</div>
</body>
</html>
this is my javascript code(ttt.js)
function val(){
var link=location.href;
var str=link.split('?');
var str1=str[1].split('&');
var str11=str1[0].split('=');
var str12=str1[1].split('=');
var temp=str11[1]+" "+str12[1];
return(temp);
}
Put your javascript at the end of your html and change document.getElementById('tr') to document.getElementById('text'). You have no element with id tr.
please look at this question and its answers, it is demonstating how to pass value from one html page to another
link
You have to do getElementById('tr') when the dom is ready and ensuring that an element with the ID exists.

Why is my script not showing input characters dynamically in a div

I want to create a TextField in which when I give any input it show on div and this script is showing inputs but not properly...
I don't know where I am making mistakes and I request that please give your answers only in JavaScript please don't use jquery. Thank you .
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>JS Bin</title>
</head>
<body>
<form name="form">
<input name="t" value="" onkeypress="printvalues();">
</form>
<div id="divId"></div>
</body>
</html>
script
function printvalues() {
var div = document.getElementById("divId");
div.innerHTML += form.t.value;
}
Here is my code with output
function printvalues() {
var div = document.getElementById("divId");
div.innerHTML = document.form.t.value;
}
EDIT:The keypress event executes before the value of textbox is changed so use keyup() event which triggers when the key is released instead like
<input name="t" value="" onkeyup="printvalues();">
Your solution is here....
Just change onkeypress to onkeyup
Made below changes and enjoy..
function printvalues(a) {
var div = document.getElementById("divId");
div.innerHTML=a;
}
<input type="text" name="t" onkeyup="printvalues(this.value);">

Why does this give "undefined" error?

I am trying to get the user to put something into the text area and the output should be what he wrote repeapiting x amount of times, but I get an error "document.forme is undefined".
Can you please help me understand why it is undefined?
My code:
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>input home work</title>
<script type="text/javascript">
var help= document.forme.tryout.value;
for (x=1; x<=10;x++){
function numberCheak (){
document.write("this is"+" "+help++);
}
}
</script>
</head>
<body>
<form name="forme">
<input name="tryout" type="text" />
<input type="button" value="click me" onClick="numberCheak();"/>
</form>
</body>
</html>
Ok, you have a few problems. The first is that you are trying to access a form element that doesn't exist yet: the script is above the form element, so the form doesn't exist when you try to get it. If you move the script to the bottom of the page it will work better.
Second, the loop should be inside the function, not wrapped around the function.
Third, document.write has weird side effects and causes the document to be rewritten and will stop the script from continuing correctly.
Here's my revised script
function numberCheak() {
var help = document.forme.tryout.value;
for (var x = 1; x <= 10; x++) {
document.getElementById("output").innerHTML += help;
}
}
and the HTML form that goes with it
<form name="forme" id="forme">
<input name="tryout" type="text" />
<input type="button" value="click me" onclick="numberCheak();" />
<span id="output"></span>
</form>
You can see it in action on jsFiddle.
Forms are stored in collection and can be accessed like this:
var form = document.forms[i];
or
var form = document.forms[name];
In your case, i is 0 and name is forme.

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