Assuming I have the following:
var s = "This is a test of the battle system."
and I had an array:
var array = [
"is <b>a test</b>",
"of the <div style=\"color:red\">battle</div> system"
]
Is there some function or way I could make it such that I can process the string s such that the output would be:
var p = "This is <b>a test</b> of the <div style=\"color:red\">battle</div> system."
Based on the arbitrary elements in the array?
Note that the array elements should be executed in sequence. So looking at the first element in array 1, find the correct place to "replace" in string "s". Then looking at array element 2, find the correct place to "replace" in string "s".
Note that the string could contain numbers, brackets, and other characters like dashes (no <> though)
Update: after Colin DeClue's remark I think you want to do something different than I originally thought.
Here is how you can accomplish that
//your array
var array = [
"is <b>a test</b>",
"of the <div style=\"color:red\">battle</div> system"
];
//create a sample span element, this is to use the built in ability to get texts for tags
var cElem = document.createElement("span");
//create a clean version of the array, without the HTML, map might need to be shimmed for older browsers with a for loop;
var cleanArray = array.map(function(elem){
cElem.innerHTML = elem;
return cElem.textContent;
});
//the string you want to replace on
var s = "This is a test of the battle system."
//for each element in the array, look for elements that are the same as in the clean array, and replace them with the HTML versions
for(var i=0;i<array.length;i++){
var idx;//an index to start from, to avoid infinite loops, see discussion with 6502 for more information
while((idx = s.indexOf(cleanArray[i],idx)) > -1){
s = s.replace(cleanArray[i],array[i]);
idx +=(array[i].length - cleanArray[i].length) +1;//update the index
}
}
//write result
document.write(s);
Working example: http://jsbin.com/opudah/9/edit
Original answer, in case this is what you meant after all
Yes. Using join
var s = array.join(" ");
Here is a working example in codepen
I suppose you've an array of original --> replacement pairs.
To extract the text from an HTML a trick that may work for you is actually creating a DOM node and then extract the text content.
Once you have the text you can use the replace method with a regular expression.
One annoying thing is that searching for an exact string is not trivial because there is no escape predefined function in Javascript:
function textOf(html) {
var n = document.createElement("div");
n.innerHTML = html;
return n.textContent;
}
var subs = ["is <b>a test</b>",
"of the <div style=\"color:red\">battle</div> system"];
var s = "This is a test of the battle system"
for (var i=0; i<subs.length; i++) {
var target = textOf(subs[i]);
var replacement = subs[i];
var re = new RegExp(target.replace(/[\\[\]{}()+*$^|]/g, "\\$&"), "g");
s = s.replace(re, replacement);
}
alert(s);
Related
I want to use vanilla js to loop through a string of html text and get its values. with jQuery I can do something like this
var str1="<div><h2>This is a heading1</h2><h2>This is a heading2</h2></div>";
$.each($(str1).find('h2'), function(index, value) {
/// console.log($(value).text());
});
using $(str) converts it to an html string as I understand it and we can then use .text() to get an element (h2)'s value.
but I want to do this within my node app on the backend rather than on the client side, because it'd be more efficient (?) and also it'd just be nice to not rely on jQuery.
Some context, I'm working on a blogging app. I want a table of contents created into an object server side.
This is another way using .innerHTML but uses the built-in iterable protocol
Here's the operations we'll need, the types they have, and a link to the documentation of that function
Create an HTML element from a text
String -> HTMLElement – provided by set Element#innerHTML
Get the text contents of an HTML element
HTMLElement -> String – provided by get Element#innerHTML
Find nodes matching a query selector
(HTMLElement, String) -> NodeList – provided by Element#querySelectorAll
Transform a list of nodes to a list of text
(NodeList, HTMLElement -> String) -> [String] – provided by Array.from
// html2elem :: String -> HTMLElement
const html2elem = html =>
{
const elem = document.createElement ('div')
elem.innerHTML = html
return elem.childNodes[0]
}
// findText :: (String, String) -> [String]
const findText = (html, selector) =>
Array.from (html2elem(html).querySelectorAll(selector), e => e.textContent)
// str :: String
const str =
"<div><h1>MAIN HEADING</h1><h2>This is a heading1</h2><h2>This is a heading2</h2></div>";
console.log (findText (str, 'h2'))
// [
// "This is a heading1",
// "This is a heading2"
// ]
// :: [String]
console.log (findText (str, 'h1'))
// [
// "MAIN HEADING"
// ]
// :: [String]
The best way to parse HTML is to use the DOM. But, if all you have is a string of HTML, according to this Stackoverflow member) you may create a "dummy" DOM element to which you'd add the string to be able to manipulate the DOM, as follows:
var el = document.createElement( 'html' );
el.innerHTML = "<html><head><title>aTitle</title></head>
<body><div><h2>This is a heading1</h2><h2>This is a heading2</h2></div>
</body</html>";
Now you have a couple of ways to access the data using the DOM, as follows:
var el = document.createElement( 'html' );
el.innerHTML = "<html><head><title>aTitle</title></head><body><div><h2>This is a heading1</h2><h2>This is a heading2</h2></div></body</html>";
// one way
el.g = el.getElementsByTagName;
var h2s = el.g("h2");
for(var i = 0, max = h2s.length; i < max; i++){
console.log(h2s[i].textContent);
if (i == max -1) console.log("\n");
}
// and another
var elementList = el.querySelectorAll("h2");
for (i = 0, max = elementList.length; i < max; i++) {
console.log(elementList[i].textContent);
}
You may also use a regular expression, as follows:
var str = '<div><h2>This is a heading1</h2><h2>This is a heading2</h2></div>';
var re = /<h2>([^<]*?)<\/h2>/g;
var match;
var m = [];
var i=0;
while ( match = re.exec(str) ) {
m.push(match.pop());
}
console.log(m);
The regex consists of an opening H2 tag followed by not a "<",followed by a closing H2 tag. The "*?" take into account zero or multiple instances of which there is at least zero or one instance.
Per Ryan of Stackoverflow:
exec with a global regular expression is meant to be used in a loop,
as it will still retrieve all matched subexpressions.
The critical part of the regex is the "g" flag as per MDN. It allows the exec() method to obtain multiple matches in a given string. In each loop iteration, match becomes an array containing one element. As each element is popped off and pushed onto m, the array m ultimately contains all the captured text values.
I have a comma-separated string being pulled into my application from a web service, which lists a user's roles. What I need to do with this string is turn it into an array, so I can then process it for my end result. I've successfully converted the string to an array with jQuery, which is goal #1. Goal #2, which I don't know how to do, is take the newly created array, and remove all characters before any array item that contains '/', including '/'.
I created a simple work-in-progress JSFiddle: https://jsfiddle.net/2Lfo4966/
The string I receive is the following:
ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC
ABCD/ in the string above can change, and may be XYZ, MNO, etc.
To convert to an array, I've done the following:
var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
Using console.log, I get the following result:
["ABCD", "ABCD/Admin", "ABCD/DataManagement", "ABCD/XYZTeam", "ABCD/DriverUsers", "ABCD/RISC"]
I'm now at the point where I need the code to look at each index of array, and if / exists, remove all characters before / including /.
I've searched for a solution, but the JS solutions I've found are for removing characters after a particular character, and are not quite what I need to get this done.
You can use a single for loop to go through the array, then split() the values by / and retrieve the last value of that resulting array using pop(). Try this:
for (var i = 0; i < currentUserRole.length; i++) {
var data = currentUserRole[i].split('/');
currentUserRole[i] = data.pop();
}
Example fiddle
The benefit of using pop() over an explicit index, eg [1], is that this code won't break if there are no or multiple slashes within the string.
You could go one step further and make this more succinct by using map():
var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',').map(function(user) {
return user.split('/').pop();
});
console.log(currentUserRole);
You can loop through the array and perform this string replace:
currentUserRole.forEach(function (role) {
role = role.replace(/(.*\/)/g, '');
});
$(document).ready(function(){
var A=['ABCD','ABCD/Admin','ABCD/DataManagement','ABCD/XYZTeam','ABCD/DriverUsers','ABCD/RISC'];
$.each(A,function(i,v){
if(v.indexOf('/')){
var e=v.split('/');
A[i]=e[e.length-1];
}
})
console.log(A);
});
You could replace the unwanted parts.
var array = ["ABCD", "ABCD/Admin", "ABCD/DataManagement", "ABCD/XYZTeam", "ABCD/DriverUsers", "ABCD/RISC"];
array = array.map(function (a) {
return a.replace(/^.*\//, '');
});
console.log(array);
var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
for(i=0;i<currentUserRole.length;i++ ){
result = currentUserRole[i].split('/');
if(result[1]){
console.log(result[1]+'-'+i);
}
else{
console.log(result[0]+'-'+i);
}
}
In console, you will get required result and array index
I would do like this;
var iur = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC',
arr = iur.split(",").map(s => s.split("/").pop());
console.log(arr);
You can use the split method as you all ready know string split method and then use the pop method that will remove the last index of the array and return the value remove pop method
var importUserRole = ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
for(var x = 0; x < currentUserRole.length; x++;){
var data = currentUserRole[x].split('/');
currentUserRole[x] = data.pop();
}
Here is a long way
You can iterate the array as you have done then check if includes the caracter '/' you will take the indexOf and substact the string after the '/'
substring method in javaScript
var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
for(var x = 0; x < currentUserRole.length; x++){
if(currentUserRole[x].includes('/')){
var lastIndex = currentUserRole[x].indexOf('/');
currentUserRole[x] = currentUserRole[x].substr(lastIndex+1);
}
}
This is my input as string
'controls: ["aa.bb.cc","dd.ee.ff"],elements: []'
I want to get the result of the data in the controls meaning :
"aa.bb.cc","dd.ee.ff"
I tried pattern
/.*(controls:.*).*/
but I didn't get all the result
I think my problem is becuase the new line
You can do it with regEx
var c = 'controls: ["aa.bb.cc", "dd.ee.ff"], elements: []';
var match = c.match(/("[a-z.]+")/g);
// or c.match(/([a-z][a-z][.][a-z][a-z][.][a-z][a-z])/);
// to strictly match letters . letters . letters
// or for a shorter match: c.match(/(\w+[.]\w+[.]\w+)/);
console.log(match); // an array of your values
EDIT:
if you only want to get the values in controls and not element, you can get the controls values out with the regEx /controls: ([\["a-z., \]]+,)/g
You could simply parse your input as a JSON object then loop throught the controls array:
var input='controls: ["aa.bb.cc", "dd.ee.ff"],
elements: []';
json = JSON.parse(input);
var controls=json.controls;
//then loop throught the controls values
for(var i=0;i<controls.length;i++){
console.log(controls[i]);
}
I think that should do it.
This might look like a very crude solution, but it works.
This expression will give you aa.bb.cc :
var res = str.match(/controls: \[(.*)\]/)[1].match(/\"(.*)\",\"(.*)\"/)[1]
and this will give the next element i.e. dd.ee.ff
var res = str.match(/controls: \[(.*)\]/)[1].match(/\"(.*)\",\"(.*)\"/)[2]
In general,
var str = "controls: [\"aa.bb.cc\",\"dd.ee.ff\"],elements: []";
var resLength = str.match(/controls: \[(.*)\]/)[1].match(/\"(.*)\",\"(.*)\"/).length;
var res = str.match(/controls: \[(.*)\]/)[1].match(/\"(.*)\",\"(.*)\"/);
for (var i=1; i<resLength; i++) {
console.log(res[i]);
}
Lets say I have the following string:
var string = "<td>123</td><td>asd</td>";
I want to take the values of the td's and put them in an array. I tried using the foreach function but my regex stops after the first closing td and gets everything between < and >.
var regex = '<([^<> ]*)([^<>]*)?>([^>]*)<\/([^<>]*)>';
var string = "<td>123</td><td>asd</td>";
var result = string.match(regex);
result.forEach(function($var){
console.log($var);
});
Output:
<td>123</td>
td
undefined
123
td
I need to manipulate the values so I can work directly in the foreach function without first splitting to an array.
Can I make this work with a regex? I can't use jQuery or append the string to the html.
Using regex alone to parse DOM is a no-no. However..
If you don't have nested <td> you can use the following code to get an array of values:
var string = "<td>123</td><td>asd</td>";
var tds = string.split("</td>");
var values = [];
for(var i=0; i<tds.length-1; i++){ //last element is empty if you split like this
values.push(tds[i].substr(4)); //ommit the "<td>"
}
alert(values);
More complex structures could be a problem and I would advise you to break the TDs up to separate ones and then extract the values using regex (/<td>(.*)</td>/g and select group 1). But for this example it works fine.
jsFiddle
Split the string with any of <td> OR </td> and reject the "".
This will work for you
var string = "<td>123</td><td>asd</td>";
var contents = string.split(/<td>|<\/td>/);
contents = contents.filter(function(el){return el != ""})
console.log(contents) //["123","asd"]
Do not parse HTML using RegExp!
Here is a jQuery version for your problem:
$("<tr/>").append("<td>123</td><td>asd</td>") // build a row with the cells
.find("td") // get the cells
.map(function() { return $(this).text(); }); // for each cell, get the content
Result: ["123", "asd"]
Edit: I see you can't use jQuery, that's unfortunate because you really need a DOM parser, and jQuery is just elegant and can do much more.
You could try the below code,
> var re = /[^<>]+(?=<\/)/g;
undefined
> var result = string.match(re);
undefined
> result.forEach(function($var){
... console.log($var);
... });
123
asd
> console.log(result);
[ '123', 'asd' ]
Explanation:
[^<>]+ Matches any character not of < or > one or more times.
(?=<\/) Lookahead asserts that anything following must be </
Avoid parsing HTML/XML with regex!
I figured out a plain way with JavaScript to do it:
function extractValues(code)
{
var tr = document.createElement('tr');
tr.innerHTML = code;
var tds = values.getElementsByTagName('td');
var values = [];
for (var i = 0; i < tds.length; i++) {
values.push(tds[i].innerHTML);
}
return values;
}
console.log(extractValues("<td>123</td><td>asd</td>"));
If you realy realy want a regex, use this:
/<td>((?:.(?!<\/td>))*.?)<\/td>/g
I had a quick question regarding RegEx...
I have a string that looks something like the following:
"This was written by <p id="auth">John Doe</p> today!"
What I want to do (with javascript) is basically extract out the 'John Doe' from any tag with the ID of "auth".
Could anyone shed some light? I'm sorry to ask.
Full story:
I am using an XML parser to pass data into variables from a feed. However, there is one tag in the XML document () that contains HTML passed into a string. It looks something like this:
<item>
<title>This is a title</title>
<description>
"By <p id="auth">John Doe</p> text text text... so on"
</description>
</item>
So as you can see, I can't use an HTML/XML parser for that p tag, because it's in a string, not a document.
Here's a way to get the browser to do the HTML parsing for you:
var string = "This was written by <p id=\"auth\">John Doe</p> today!";
var div = document.createElement("div");
div.innerHTML = string; // get the browser to parse the html
var children = div.getElementsByTagName("*");
for (var i = 0; i < children.length; i++)
{
if (children[i].id == "auth")
{
alert(children[i].textContent);
}
}
If you use a library like jQuery, you could hide the for loop and replace the use of textContent with something cross-browser.
No need of regular expressions to do this. Use the DOM instead.
var obj = document.getElementById('auth');
if (obj)
{
alert(obj.innerHTML);
}
By the way, having multiples id with the same value in the same page is invalid (and will surely result in odd JS behavior).
If you want to have many auth on the same page use class instead of id. Then you can use something like:
//IIRC getElementsByClassName is new in FF3 you might consider using JQuery to do so in a more "portable" way but you get the idea...
var objs = document.getElementsByClassName('auth');
if (objs)
{
for (var i = 0; i < objs.length; i++)
alert(obj[i].innerHTML);
}
EDIT: Since you want to parse a string that contain some HTML, you won't be able to use my answer as-iis. Will your HTML string contain a whole HTML document? Some part? Valid HTML? Partial (broken) HTML?
Perhaps something like
document.getElementById("auth").innerHTML.replace(/<^[^>]+>/g, '')
might work. innerHTML is supported on all modern browsers. (You may omit the replace if you don't care about removing HTML bits from the inner content.)
If you have jQuery at your disposal, just do
$("#auth").text()
What I want to do (with javascript) is
basically extract out the 'John Doe'
from any tag with the ID of "auth".
You can't have the same id (auth) for more than one element. An id should be assigned once per element per page.
If, however, you assign a class of auth to elements, you can go about something like this assuming we are dealing with paragraph elements:
// find all paragraphs
var elms = document.getElementsByTagName('p');
for(var i = 0; i < elms.length; i++)
{
// find elements with class auth
if (elms[i].getAttribute('class') === 'auth') {
var el = elms[i];
// see if any paragraph contains the string
if (el.innerHTML.indexOf('John Doe') != -1) {
alert('Found ' + el.innerHTML);
}
}
}
Assuming you only have 1 auth per string, you might go with something like this:
var str = "This was written by <p id=\"auth\">John Doe</p> today!",
p = str.split('<p id="auth">'),
q = p[1].split('</p>'),
a = q[0];
alert(a);
Simple enough. Split your string on your paragraph, then split the second part on the paragraph close, and the first part of the result will be your value. Every time.
If the content of the tag contains only text, you could use this:
function getText (htmlStr, id) {
return new RegExp ("<[^>]+\\sid\\s*=\\s*([\"'])"
+ id
+ "\\1[^>]*>([^<]*)<"
).exec (htmlStr) [2];
}
var htmlStr = "This was written by <p id=\"auth\">John Doe</p> today!";
var id = "auth";
var text = getText (htmlStr, id);
alert (text === "John Doe");