<!DOCTYPE html>
<html>
<head>
<title>input number</title>
</head>
<body>
enter no:1<input id="t1" type="text"><br>
<button type="button" onClick="myFunction()">submit</button>
<button type="button" onClick="myFunction()">next</button>
<div id="div1" style="color:#0000FF">
</div>
<script>
function myFunction(){
var no=document.getElementById("t1").value;
if(no==""||isNaN(no))
{
alert("Not Numeric");
}
else{
if(no!=1){
if(no%2==0){
no=no/2;
}
if (no%2!=0) {
no=(no*3)+1;
}
}
}
document.getElementById("div1").innerHTML = no;
}
</script>
</body>
</html>
After entering number in the text box when I press submit button it shows the following output
enter no:1
submit next
16
but when i press next button it is not showing any output.My expected output is when I press next button it shoult show the next no. by executing the logic in the myFunction() function.Helpme...
You haven't set any case for when no = 1. You have a case for when no != 1 and when no%2 != 0 both of which are false when no = 1. There isn't any increment logic in here to find the next number and return it. I think you are missing a } at the end of the no%2==0 clause.
Also I fail to see why you have two identical buttons here, next and submit do the same thing. Moreover I would advice more descriptive IDs. div1 isn't a good name for a div.
The javascript part should look like this, if the intention is to implement Collatz conjecture. http://en.wikipedia.org/wiki/Collatz_conjecture
function myFunction(){
var no=document.getElementById("t1").value;
if(no==""||isNaN(no)) {
alert("Not Numeric");
} else {
if(no!=1) {
if(no%2==0) {
no=no/2; // Note the division operator instead of mod
} else {
no=(no*3)+1;
}
}
}
document.getElementById("t1").value = no; // Note that we are writing to the textbox
}
There are some basic HTML issues too, in your post you are using the input tag as
<input id="t1" type="text"> use it as: <input id="t1" type="text" />
Secondly, when you submit the data to the function, you are having some value there! Maybe 1 is the value or 16, whatever. But when you are trying to resubmit, either its not allowed or your input is now an empty field. So the function is not executing further than this step:
if(no==""||isNaN(no))
Try to save the value in the form.
Try using this:
document.getElementById("t1").value = no;
Make sure that the value is captured as it was, because your code is changing the value into some other form, use a new variable for this. That would save the value from the input and again write it back to that input.
This will set the value for that text input as it was before the function. It might make the input again ready for the submit!
Related
Not really sure how to phrase the question but I have created a function where if a button is disabled, the textbox below should also be disabled, but it's not. Here's the code:
<script>
function Play(){
if (document.getElementById("high").value > document.getElementById("low").value){
document.getElementById("myBtn").disabled = false;}
else {document.getElementById("myBtn").disabled = true;
document.getElementById("ErrorForPlay").innerHTML = "Numbers Wrong."}
}
</script> //this script checks to see if the higher number is less than the lower number. Will be disabled if so.
<br>
<button id="myBtn" onclick="Play()">Play</button>
<span id="ErrorForPlay"> </span>
<!--assume that the button on top is always disabled-->
GUESS: <!--But the textbox does not disable-->
<br>
<Input type="number" id="guess" onclick="dataValidationG()" onchange="dataValidationG()"> </Input>
<button id="submit">Enter Guess</button>
<script>
function dataValidationG(){
if (document.getElementById("myBtn").disabled = true;){
document.getElementById("guess").disabled = true;}
else {document.getElementById("guess").disabled = false;}
//script to check. If Button "myBtn" is disabled, the text should also disable if not, the text should be enabled.
}
</script>
I'm sure it has something to do with the javascript but I can't place where did I go wrong/what's missing. (I'm also only allowed to do everything under 1 html file.)
The problem is in your if statement conditions, you are using = and not ==.
And thanks to JavaScript being such a nice programming language, it doesn't throw a syntax error, but instead sets the value inside the if statement condition!
So just replace the = with == inside your if statement conditions.
Please note that i am a beginner in javascript. I've googled all the possible terms for my question but no luck. I wanted to know if there exists a javascript function that can be used to check if a field has been populated with data using another javascript function. No libraries please since i want to know the basics of javascript programming.
Edit:
I just wanted to clarify that scenario that i am into.
I have 3 input fields. These fields have their value assigned automatically by another javascript function. What i wanted to do is when this fields have their respected values i wanted to create a new input field that will calculate the sum of the value of the 3 fields.
As You are new Please try this whole code of HTML with Javascript code too.
<!DOCTYPE html>
<html>
<head>
<script>
function copyText()
{
var TextValue = document.getElementById("field1").value
if(TextValue !=''){
alert(TextValue);
}
alert();
}
</script>
</head>
<body>
<input type="text" id="field1" value="Hello World!"><br>
<button onclick="copyText()">Copy Text</button>
</body>
</html>
Hope this works.
Hope this helps you
//Html Code
<input type="text" value="sdsd" onChange="checkValue(this.value)">
//Java Script Code
function checkValue(value){
if((value).trim()!==""){
alert('return true');
}
else{
alert('return false');
}
}
//HTML line:
<input type="text" id="txtAddress" />
//JS code:
function setValue() {
//first we set value in text field:
document.getElementById('txtAddress').value = 'new value';
TestFunction();
}
function TestFunction() {
//second we will get value from this filed and check wether it contains data or not:
var address = document.getElementById('txtAddress').value;
if (address != "") {
alert("Yes, field contains address");
}
else {
alert("Empty field, there is no address");
}
}
I'm not sure what are you trying to achieve.
If you want to check if the input to the field was made with Javascript : there's no way to make that UNLESS your Javascript input function stores such information in some place (for example, add specific class to the modified object). Then you can proceed with following:
If you want to check if there's any value in the field then you can use onchange (triggers on change, you can pass the object to the function and get every property attached to it - value, class etc.).
example:
function changeValue( object )
{
object.value = "new value";
object.classList.add("modified");
}
function isChanged( object )
{
if( object.classList.contains("modified") )
alert("I'm modified by JS!");
}
<input type="text" id="first" onchange="isChanged(this)">
It has been some time since I was writing JS, but this should work.
Edit: now I remember onchange triggers only, if element is edited by user, thus rendering onchange detection worthless. Well, you could use set interval with the following function:
function getModified() {
// somehow process with
// document.getElementsByClassName("modified");
}
setInterval( getModified(), 3000 ); // get JS modified elements every 3s
lets say this is your html field (text input for instance):
<input type="text" id="txtName" />
in order to get it's value with javascript, use document.getElementById('txtName').value - for example:
function alert_value() {
var value = document.getElementById('txtName').value;
alert(value);
}
hope that helps.
EDIT:
if this text field is added dynamically, i'd suggest including jQuery and set the following script:
$(function(){
$(document).on('keyup', '#txtName', function(){ alert($(this).val()) });
});
**Below is the input text fileds**
<form:form commandName="DRCNdetails" id="frm1" method="POST" action="addNewDelayReason.do" >
<form:input id="text1" path="delayCategory" cssClass="padR10 boxSizing" maxlength="75"></form:input>
<form:input path="preFix" id="text2" cssClass="padR10 boxSizing" maxlength="6"> </form:input>
<form:input path="reasonValue" maxlength="150" id="reasonValue" cssClass="textbox width100" cssStyle="visibility:hidden"></form:input>
</form:form> <button class="btnStyle blueBtn" onclick="formvalidation(),validateSpecialCharacters()"> <span class="left">
Submit
on submit need to vaidate the id's "text1","text2" fileds , on successful validation should display the below pop up screen that is showLtBox('mask', 'addMisdReasonCode1'), the conditions are below:
should not allow the null values for both the fileds, and special characters,and integers and alert me accordingly , on satisying this criteria only it should display the pop up screen showLtBox('mask', 'addMisdReasonCode1')
As far as I understand the question, you need to create a validation function that would be triggered upon pressing the submit button.
I already see that you have created to function that would be triggered on "OnClick" operation, However the syntax is incorrect.
You need to separate between the two function using ";" and not ","
You need to use only one function for validation - this would be more readable than the code you have written.
The result should be returned to the onclick command.
Example:
change the attribute onclick as follows:
onclick="return FullValidation();"
Create new JavaScript function that includes the two validations and return validation result;
function FullValidation() {
var validationResultOK = formvalidation();
if (validationResultOK) {
validationResultOK = validateSpecialCharacters();
}
if (validationResultOK) {
// Popup alert should be here, I put alert as example.
alert("Out your message here");
}
return validationResultOK;
}
Use Javascript Regular expression..
var pattern = new RegExp(/^[a-zA-Z]{n}$/);
where n is number of charecters you want to accept.
the above regular expression matches only charecters(both cases).
Now retrieve the value from your text fields
var text1 = document.getElementById("#your_id").value;
var text2 = document.getElementById("#your_id").value;
if(pattern.test(text1) && pattern.test(text2))
{
// your popup code
}
I have text file. there around 1000 lines in it, each line contains a 8 letter alpha numeric word for example my text file looks like this
TEST1234
T1E2A334
12RR8912
and so on. this file is located on the server in a folder called TestCodes
Now I have an html file called test.html where in this file I have input textbox where the user enters the testcode he/she has with them
I have button called Verify. when this input button is clicked I want to check the user inputed value against the contents in the text file.
If the testcode exists in the text file then display a button called Procced if not display an error message called invalid.
I know how to write the if condition but I have no idea how to check it against the text file
HTML
<div class="user-input">
<input type="text" name="test-code" id="test-code" value="" />
<input type="submit" value="Verify Code" name="verify-code" id="verify-code" />
</div>
<div id="TestRegister">
<form id="club" action="/Proceed.html" method="post" autocomplete="off">
<input type="submit" value="Proceed Registration" name="proceed-register" />
</form>
</div>
<div id="TestError">
<span>Please check the code again, its not valid</span>
</div>
JavaScript
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript">
$(document).ready(function () {
$("#TestRegister").hide();
$("#TestError").hide();
$.get("testcodes.txt", function (data) {
var lines = data.split("\n");
// this is where I am stuck. how to pass the above to ARRAY
$("#verify-code").click(function (e) {
e.preventDefault();
if ( /* here I need to check against the user input value, if they are equal */ ) {
$("#TestRegister").show();
$("TestError").hide();
} else {
$("#TestRegister").hide();
$("TestError").show();
}
}
});
</script>
How can I pass text from testcodes to an Array and then check the user input value against this array? If the user input value is present in the array then I want to show #TestRegister, and if not, or if the input value is blank or null, show #TestError.
Thanks and appreciate any tips.
var lines;
$(document).ready(function () {
$("#TestRegister").hide();
$("#TestError").hide();
$.get("testcodes.txt", function (data) {
lines = data.split("\n");
});
$("#verify-code").click(function (e) {
e.preventDefault();
if (lines.indexOf($("#test-code").val()) !== -1 && $("#test-code").val().length == 8) {
$("#TestRegister").show();
$("TestError").hide();
} else {
$("#TestRegister").hide();
$("TestError").show();
}
});
});
You can avoid an array loop altogether by creating a regular expression that ensures the test code is found between word boundaries:
var codeRegEx = new RegExp('\\b'+$('#test-code').val()+'\\b');
if(codeRegEx.test(lines)) {
// the testcode is found on a single line, avoiding partial matches
}
Here's a demo:
jsFiddle DEMO
I can't believe that I can't find the answer to this question but I really have searched and can't find it! honest!
anyway - here is the question: I am trying to create a validation function for a form that will not permit the user to proceed to the next form field if the field doesn't validate.
I just want the 'incorrect' field to have focus until it is 'correct'.
because this is for a JS class I cannot use jQuery or any other framework.
here is one of the HTML fields:
<li>Number 1:<input class="field2" type="text" id="star1" onchange="validateAndDraw(this.value);"></li>
and here is a truncated version of the JS function:
function validateAndDraw(theValue) {
if (isNaN(theValue)) {
alert("no good");
} else {
[do stuff here]
}
}
I have tried using 'this.focus();' and 'this.parentNode.focus();' but no joy.
I am sure the answer is ridiculously simple, but I can't seem to find it.
thanks,
bennett
Try sending the object reference to the function instead of the value.
So in your input event:
validateAndDraw(this);
And change your function to:
function validateAndDraw(input) {
if (isNaN(input.value)) {
alert("no good");
input.focus();
} else {
[do stuff here]
}
}
As a side, I would suggest looking into Progressive Enhancement.
document.getElementById('star1').focus();
Using this inside your function will refer back to the function.
Alternatively, you could pass the object in the onclick event:
<input class="field2" type="text" id="star1" onchange="validateAndDraw(this);">
so the function could look like
function validateAndDraw(obj) {
alert(obj.value);
}
Try calling focus() in the blur event.
Also, this in your function refers to the global context, not the element.
(It only refers to the element inside the inline handler; you are making an ordinary function call from there)
You should change your function to accept the element as a parameter (which you can pass as this insidethe inline handler)
Why not pass in the element?
function validateAndDraw(theElement) {
var theValue = theElement.value;
if (isNaN(theValue)) {
alert("no good");
theElement.focus()
} else {
[do stuff here]
}
}
Send as trigger
There are for each loop function for check input in form.
If there are input[x].value = "", so alert and focus in it, next input and next alert
<html>
<body>
<form onsubmit="return validateForm(this)">
Name: <input type="text" name="name"><br />
E-mail: <input type="text" name="email"><br />
Password: <input type="password" name="password"><br />
<input type="submit" value="Send">
</form>
<script >
function validateForm(input) {
for (x in input) {
if (input[x].value == "") {
alert(input[x].name + " must be filled out");
input[x].focus();
return false;
}
}
}
</script>
</body>
</html>