I am looking for a way to find instances of a certain character within a certain element. I am aware of doing something like:
var string = 'this is a string';
string.indexOf('a');
however, i want indexOf to look at a particular tag within a particular html file. (in this case, p tags). I have commented out what i tried to use in order to achieve this.
function findQuestion() {
// var string1 = document.getElementsByTagName('p');
var string2 = '??';
if (string2.indexOf('?') !== -1) {
console.log('foundQuestion');
}
else {
console.log('nothing');
}
}
findQuestion();
This code obviously just checks to see that there is a '?' in string2, but how do i write this to find all instances of '?' within p tags and return all content preceding that up to the opening p tag in which the '?' was found?
thanks.
How you could do that:
Get all p elements.
Create an empty array, results
Iterate over them and check for each p element
If the p's innerHTML contains a question mark split the string at the question mark, get the first part and add a question mark. Then add this new string to the results array
Return the results array
Example Code:
function findQuestion() {
var ps = document.getElementsByTagName('p');
var result = [];
for(var i = 0; i < ps.length; i++){
var p = ps[i];
if (p.innerHTML.indexOf('?') !== -1) {
result.push(p.innerHTML.split("?")[0] + "?");
}
}
return result;
}
findQuestion();
http://jsfiddle.net/3o4tcchL/1/
Use a loop condition to check the entirety of the content within , after that use something like slice, which will grab everything up to a particular index you specify.
Related
My goal's create a filter search function, in particular actually I'm using .indexOf method that allow me to check if two string are equal. The problem's that if I've the compare string with space break like this: Hair Cut.
Example:
String to search: Hair
String contained in the object: Hair Cut
var cerca = $('#filter_service').val();
for(var i = 0; i < GlobalVariables.availableServices.length; i++) {
if (cerca.toLowerCase().contains(GlobalVariables.availableServices[i].name.toLowerCase()) != -1) {
console.log(GlobalVariables.availableServices[i].name)
}
}
How you can see I valorize the variable cerca that contains the string Hair in the example. I compare this with an object variable, how I said, the problem is if I insert the string Hair I get no response in console, also if I insert the string with break space like the compare string Hair Cut I get the console response.
How I can print a result also when the variable cerca is equal to the first character of the compair string? In particular Hai?
I don't know if I was clear, hope yes.
.contains() is for checking DOM element children. You said above that you are using .indexOf to check, but it doesn't look like you use it in your code?
var cerca = $('#filter_service').val();
var searchIn;
for(var i = 0; i < GlobalVariables.availableServices.length; i++) {
searchIn = GlobalVariables.availableServices[i].name.toLowerCase().split(' ');
for (j = 0; j < searchIn.length; j++) {
if (cerca.toLowerCase().split(' ').indexOf(searchIn[j].toLowerCase()) >= 0) {
console.log(GlobalVariables.availableServices[i].name);
}
}
}
$('#filter_service').on('input', function() {
var inputStr = $('#filter_service').val();
var similar = [];
for (i = 0; i < GlobalVariables.availableServices.length; i++) {
if (GlobalVariables.availableServices[i].name.toLowerCase().indexOf(inputStr.toLowerCase) >= 0) {
similar[similar.length] = GlobalVariables.availableServices[i].name;
}
}
// At this point, you can do whatever you want with the similar service
// names (all of the possible result names are included in the array, similar[].)
});
I can't test that code right now, but in theory, it should work.
Here is a JSFiddle demo:
http://jsfiddle.net/MrGarretto/vrp5pghr/
EDIT: Updated and fixed my errors
EDIT 2: Added the 'possible results' solution
EDIT 3: Added a JSFiddle
can you please take a look at this code and let me know why I am not able to add the array Items into the .box? I already used the .text() and .html()
var letters = [];
var str = "A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";
var letters = str.split(",");
for (var j = 0; j <letters.length; j++) {
$(".box").html(letters[j]);
}
but they only add the last item "Z" into the box
You need to use .append() because .html() will replace the whole html everytime
Because you're using .html() which replaces any pre-existing text with the new text.
Use .append() instead:
$(".box").append(letters[j]);
.html() will replace the content at the each iteration of loop. In first iteration 'A' will be placed into (".box") and int second iteration 'B' will be replaced by 'A' and so on. When loop ends the last letter 'Z' will be the only content in ('.box'). if youy want to add all letters in ('.box') use .append()
see link : http://api.jquery.com/append/
That's because html doesn't append but replaces the content.
A solution could be to use append instead of html but that's slow if you have a big array. In such a case, the best practice is to build the HTML in one go :
$(".box").html(letters.join(''));
If what you want is to have a delay between the box being changed, you can use setTimeout :
(function step(){
var letter = letters.shift();
if (!letter) return;
$('.box').html(letter)
setTimeout(step,200);
})()
You will need a delay in updating the box in order to show the letters one after the other:
var str = "A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";
var letters = str.split(",");
next();
function next() {
if( letters && letters.length) {
$(".box").text(letters.shift());
window.setTimeout(next, 500);
}
}
imagine this html on a page
<div id="hpl_content_wrap">
<p class="foobar">this is one word and then another word comes in foobar and then more words and then foobar again.</p>
<p>this is a link with foobar in an attribute but only the foobar inside of the link should be replaced.</p>
</div>
using javascript, how to change all 'foobar' words to 'herpderp' without changing any inside of html tags?
ie. only plain text should be changed.
so the successful html changed will be
<div id="hpl_content_wrap">
<p class="foobar">this is one word and then another word comes in herpderp and then more words and then herpderp again.</p>
<p>this is a link with herpderp in an attribute but only the herpderp inside of the link should be replaced. </p>
</div>
Here is what you need to do...
Get a reference to a bunch of elements.
Recursively walk the children, replacing text in text nodes only.
Sorry for the delay, I was sidetracked before I could add the code.
var replaceText = function me(parentNode, find, replace) {
var children = parentNode.childNodes;
for (var i = 0, length = children.length; i < length; i++) {
if (children[i].nodeType == 1) {
me(children[i], find, replace);
} else if (children[i].nodeType == 3) {
children[i].data = children[i].data.replace(find, replace);
}
}
return parentNode;
}
replaceText(document.body, /foobar/g, "herpderp");
jsFiddle.
It's a simple matter of:
identifying all text nodes in the DOM tree,
then replacing all foobar strings in them.
Here's the full code:
// from: https://stackoverflow.com/questions/298750/how-do-i-select-text-nodes-with-jquery
var getTextNodesIn = function (el) {
return $(el).find(":not(iframe)").andSelf().contents().filter(function() {
return this.nodeType == 3;
});
};
var replaceAllText = function (pattern, replacement, root) {
var nodes = getTextNodesIn(root || $('body'))
var re = new RegExp(pattern, 'g')
nodes.each(function (i, e) {
if (e.textContent && e.textContent.indexOf(pattern) != -1) {
e.textContent = e.textContent.replace(re, replacement);
}
});
};
// replace all text nodes in document's body
replaceAllText('foobar', 'herpderp');
// replace all text nodes under element with ID 'someRootElement'
replaceAllText('foobar', 'herpderp', $('#someRootElement'));
Note that I do a precheck on foobar to avoid processing crazy long strings with a regexp. May or may not be a good idea.
If you do not want to use jQuery, but only pure JavaScript, follow the link in the code snippet ( How do I select text nodes with jQuery? ) where you'll also find a JS only version to fetch nodes. You'd then simply iterate over the returned elements in a similar fashion.
I need to get the ID of an element but the value is dynamic with only the beginning of it is the same always.
Heres a snippet of the code.
<form class="form-poll" id="poll-1225962377536" action="/cs/Satellite">
The ID always starts with poll- then the numbers are dynamic.
How can I get the ID using just JavaScript and not jQuery?
You can use the querySelector for that:
document.querySelector('[id^="poll-"]').id;
The selector means: get an element where the attribute [id] begins with the string "poll-".
^ matches the start
* matches any position
$ matches the end
jsfiddle
Try this.
function getElementsByIdStartsWith(container, selectorTag, prefix) {
var items = [];
var myPosts = document.getElementById(container).getElementsByTagName(selectorTag);
for (var i = 0; i < myPosts.length; i++) {
//omitting undefined null check for brevity
if (myPosts[i].id.lastIndexOf(prefix, 0) === 0) {
items.push(myPosts[i]);
}
}
return items;
}
Sample HTML Markup.
<div id="posts">
<div id="post-1">post 1</div>
<div id="post-12">post 12</div>
<div id="post-123">post 123</div>
<div id="pst-123">post 123</div>
</div>
Call it like
var postedOnes = getElementsByIdStartsWith("posts", "div", "post-");
Demo here: http://jsfiddle.net/naveen/P4cFu/
querySelectorAll with modern enumeration
polls = document.querySelectorAll('[id ^= "poll-"]');
Array.prototype.forEach.call(polls, callback);
function callback(element, iterator) {
console.log(iterator, element.id);
}
The first line selects all elements in which id starts ^= with the string poll-.
The second line evokes the enumeration and a callback function.
Given that what you want is to determine the full id of the element based upon just the prefix, you're going to have to do a search of the entire DOM (or at least, a search of an entire subtree if you know of some element that is always guaranteed to contain your target element). You can do this with something like:
function findChildWithIdLike(node, prefix) {
if (node && node.id && node.id.indexOf(prefix) == 0) {
//match found
return node;
}
//no match, check child nodes
for (var index = 0; index < node.childNodes.length; index++) {
var child = node.childNodes[index];
var childResult = findChildWithIdLike(child, prefix);
if (childResult) {
return childResult;
}
}
};
Here is an example: http://jsfiddle.net/xwqKh/
Be aware that dynamic element ids like the ones you are working with are typically used to guarantee uniqueness of element ids on a single page. Meaning that it is likely that there are multiple elements that share the same prefix. Probably you want to find them all.
If you want to find all of the elements that have a given prefix, instead of just the first one, you can use something like what is demonstrated here: http://jsfiddle.net/xwqKh/1/
I'm not entirely sure I know what you're asking about, but you can use string functions to create the actual ID that you're looking for.
var base = "common";
var num = 3;
var o = document.getElementById(base + num); // will find id="common3"
If you don't know the actual ID, then you can't look up the object with getElementById, you'd have to find it some other way (by class name, by tag type, by attribute, by parent, by child, etc...).
Now that you've finally given us some of the HTML, you could use this plain JS to find all form elements that have an ID that starts with "poll-":
// get a list of all form objects that have the right type of ID
function findPollForms() {
var list = getElementsByTagName("form");
var results = [];
for (var i = 0; i < list.length; i++) {
var id = list[i].id;
if (id && id.search(/^poll-/) != -1) {
results.push(list[i]);
}
}
return(results);
}
// return the ID of the first form object that has the right type of ID
function findFirstPollFormID() {
var list = getElementsByTagName("form");
var results = [];
for (var i = 0; i < list.length; i++) {
var id = list[i].id;
if (id && id.search(/^poll-/) != -1) {
return(id);
}
}
return(null);
}
You'll probably have to either give it a constant class and call getElementsByClassName, or maybe just use getElementsByTagName, and loop through your results, checking the name.
I'd suggest looking at your underlying problem and figure out a way where you can know the ID in advance.
Maybe if you posted a little more about why you're getting this, we could find a better alternative.
You use the id property to the get the id, then the substr method to remove the first part of it, then optionally parseInt to turn it into a number:
var id = theElement.id.substr(5);
or:
var id = parseInt(theElement.id.substr(5));
<form class="form-poll" id="poll-1225962377536" action="/cs/Satellite" target="_blank">
The ID always starts with 'post-' then the numbers are dynamic.
Please check your id names, "poll" and "post" are very different.
As already answered, you can use querySelector:
var selectors = '[id^="poll-"]';
element = document.querySelector(selectors).id;
but querySelector will not find "poll" if you keep querying for "post": '[id^="post-"]'
If you need last id, you can do that:
var id_list = document.querySelectorAll('[id^="image-"]')
var last_id = id_list.length
alert(last_id)
I am looping through an array of english phrases, and if i find a match, with the current text node, i replace it with it's translation in the non_english array. All of that works 100% for exact matches.
But for partial matches, I need to use the .match command, which allows for partial matches.
My code to search for exact matches is like this:
var found = $.inArray(value,en_lang);
Then if there is a found value, then do replacement of text. This method is fast and I love it.
However to do partial word/phrase matching, I have to use this looping code.
// loop thru language arrays
for (var x = en_count; x > 0; x--) {
// assign current from/to variables for replace
var from = en_lang[x];
var to = other_lang[x];
// if value match do translation
if (value.match(from)) {
content(node, value.replace(from, to));
}
// mark this node as translated
if ($.browser.msie == 'false') {
$(node).data('translated', 'yes');
}
}
This does the job but is pretty slow. After a lot of research, I have found that I can convert the english array to a list-based string via the join command.
But I am unable to come up with a function to search this list for a partial match, and return the position in the list.
I was trying out this old js function created in 2006. But I can't figure out how to get the position back, correctly.
function listfind(list, value, delimiters) {
if (!delimiters) {
var delimiters = ','
}
_TempListSplitArray = list.split(delimiters)
var FoundIdx = 0;
for (i = 0; i < _TempListSplitArray.length; i++) {
if (_TempListSplitArray[i] == value) {
FoundIdx = i + 1;
break
}
if (value.match(_TempListSplitArray[i])) {
FoundIdx = i + 1;
break
}
}
return FoundIdx
}
Thank you for your time.
Javascript has a foreach type of system but its still based on a loop
var array = ['hello', 'world'];
for(var key in array){
alert(array[key]);
}
Thats the best your getting for looping though an array but this way allso works with objects
var obj = {'one':'hello', 'two':'world'];
for(var key in obj){
alert("key: "+key+" value: "+obj[key]);
}
UPDATED for Comments on your question
You can just replace the text you know
var str = "hello World";
str = str.replace("hello", "Bye bye");
alert(str);