Develop Reference

JS What's the fastest way to display one specific line of a list?

In my Javascript code, I get one very long line as a string.
This one line only has around 65'000 letters. Example:
config=123&url=http://localhost/example&path_of_code=blablaba&link=kjslfdjs...
What I have to do is replace all & with an break (\n) first and then pick only the line which starts with "path_of_code=". This line I have to write in a variable.
The part with replace & with an break (\n) I already get it, but the second task I didn't.
var obj = document.getElementById('div_content');
var contentJS= obj.value;
var splittedResult;
splittedResult = contentJS.replace(/&/g, '\n');
What is the fastest way to do it? Please note, the list is usually very long.

It sounds like you want to extract the text after &path_of_code= up until either the end of the string or the next &. That's easily done with a regular expression using a capture group, then using the value of that capture group:
var rex = /&path_of_code=([^&]+)/;
var match = rex.exec(theString);
if (match) {
var text = match[1];
}
Live Example:
var theString = "config=123&url=http://localhost/example&path_of_code=blablaba&link=kjslfdjs...";
var rex = /&path_of_code=([^&]+)/;
var match = rex.exec(theString);
if (match) {
var text = match[1];
console.log(text);
}

Use combination of String.indexOf() and String.substr()
var contentJS= "123&url=http://localhost/example&path_of_code=blablaba&link=kjslfdjs...";
var index = contentJS.indexOf("&path_of_code"),
substr = contentJS.substr(index+1),
res = substr.substr(0, substr.indexOf("&"));
console.log(res)

but the second task I didn't.
You can use filter() and startsWith()
splittedResult = splittedResult.filter(i => i.startsWith('path_of_code='));

Replace string with condition in google script

in google script I am trying to replace a %string basing on the character following it.
I've tried using:
var indexOfPercent = newString.indexOf("%");
and then check the character of indexOfPercent+1, but indexOf returns only the first occurrence of '%'.
How can I get all occurrences? Maybe there is easier way to do that (regular expressions)?
EDIT:
Finally I want to replace all my % occurrences to %%, but not if percent sign was part of %# or %#.
To sum up: my string: Test%# Test2%s Test3%. should look like: Test%# Test2%s Test3%%.
I've tried using something like this:
//?!n Matches any string that is not followed by a specific string n
//(x|y) Find any of the alternatives specified
var newString = newString.replace(\%?![s]|\%?![%], "%%")
but it didn't find any strings. I am not familiar with regex's, so maybe it is a simple mistake.
Thanks

Try this code:
// replace all '%'
var StrPercent = '%100%ffff%';
var StrNoPersent = StrPercent.replace(/\%/g,'');
Logger.log(StrNoPersent); // 100ffff
Look for more info here
Edit
In your case you need RegEx with the character not followed by group of characters. Similiar question was asked here:
Regular expressions - how to match the character '<' not followed by ('a' or 'em' or 'strong')?
Thy this code:
function RegexNotFollowedBy() {
var sample = ['Test%#',
'Test2%s',
'Test3%',
'%Test4%'];
var RegEx = /%(?!s|#)/g;
var Replace = "%%";
var str, newStr;
for (var i = 0; i < sample.length; i++) {
str = sample[i];
newStr = str.replace(RegEx, Replace);
Logger.log(newStr);
}
}
I'll explain expression /%(?!s|#)/g:
% -- look '%'
(text1|text2|text3...|textN) -- not followed by text1, 2 etc.
g -- look for any accurance of searched text

Split a string of HTML into an array by particular tags

Given this HTML as a string "html", how can I split it into an array where each header <h marks the start of an element?
Begin with this:
<h1>A</h1>
<h2>B</h2>
<p>Foobar</p>
<h3>C</h3>
Result:
["<h1>A</h1>", "<h2>B</h2><p>Foobar</p>", "<h3>C</h3>"]
What I've tried:
I wanted to use Array.split() with a regex, but the result splits each <h into its own element. I need to figure out how to capture from the start of one <h until the next <h. Then include the first one but exclude the second one.
var html = '<h1>A</h1><h2>B</h2><p>Foobar</p><h3>C</h3>';
var foo = html.split(/(<h)/);
Edit: Regex is not a requirement in anyway, it's just the only solution that I thought would work for generally splitting HTML strings in this way.

In your example you can use:
/
<h // Match literal <h
(.) // Match any character and save in a group
> // Match literal <
.*? // Match any character zero or more times, non greedy
<\/h // Match literal </h
\1 // Match what previous grouped in (.)
> // Match literal >
/g
var str = '<h1>A</h1><h2>B</h2><p>Foobar</p><h3>C</h3>'
str.match(/<h(.)>.*?<\/h\1>/g); // ["<h1>A</h1>", "<h2>B</h2>", "<h3>C</h3>"]
But please don't parse HTML with regexp, read RegEx match open tags except XHTML self-contained tags

From the comments to the question, this seems to be the task:
I'm taking dynamic markdown that I'm scraping from GitHub. Then I want to render it to HTML, but wrap every title element in a ReactJS <WayPoint> component.
The following is a completely library-agnostic, DOM-API based solution.
function waypointify(html) {
var div = document.createElement("div"), nodes;
// parse HTML and convert into an array (instead of NodeList)
div.innerHTML = html;
nodes = [].slice.call(div.childNodes);
// add <waypoint> elements and distribute nodes by headings
div.innerHTML = "";
nodes.forEach(function (node) {
if (!div.lastChild || /^h[1-6]$/i.test(node.nodeName)) {
div.appendChild( document.createElement("waypoint") );
}
div.lastChild.appendChild(node);
});
return div.innerHTML;
}
Doing the same in a modern library with less lines of code is absolutely possible, see it as a challenge.
This is what it produces with your sample input:
<waypoint><h1>A</h1></waypoint>
<waypoint><h2>B</h2><p>Foobar</p></waypoint>
<waypoint><h3>C</h3></waypoint>

I'm sure someone could reduce the for loop to put the angle brackets back in but this is how I'd do it.
var html = '<h1>A</h1><h2>B</h2><p>Foobar</p><h3>C</h3>';
//split on ><
var arr = html.split(/></g);
//split removes the >< so we need to determine where to put them back in.
for(var i = 0; i < arr.length; i++){
if(arr[i].substring(0, 1) != '<'){
arr[i] = '<' + arr[i];
}
if(arr[i].slice(-1) != '>'){
arr[i] = arr[i] + '>';
}
}
Additionally, we could actually remove the first and last bracket, do the split and then replace the angle brackets to the whole thing.
var html = '<h1>A</h1><h2>B</h2><p>Foobar</p><h3>C</h3>';
//remove first and last characters
html = html.substring(1, html.length-1);
//do the split on ><
var arr = html.split(/></g);
//add the brackets back in
for(var i = 0; i < arr.length; i++){
arr[i] = '<' + arr[i] + '>';
}
Oh, of course this will fail with elements that have no content.

Hi I used this function to convert html String Dom in array
static getArrayTagsHtmlString(str){
let htmlSplit = str.split(">")
let arrayElements = []
let nodeElement =""
htmlSplit.forEach((element)=>{
if (element.includes("<")) {
nodeElement = element+">"
}else{
nodeElement = element
}
arrayElements.push(nodeElement)
})
return arrayElements
}
Happy code

Removing last comma

I read content from a file and then write it another file after editing . While editing , for each read line i put a comma at the end of line and then write it to the file. For the last read line i do not want to write a comma. How should i do it.?
while(!inputFile.AtEndOfStream){
var readLine = inputFile.ReadLine();
var omitChars = new RegExp("#define").test(readLine);
if(omitChars==1){
var stringReadPosition = readLine.substr(8);
var finalString = stringReadPosition.replace(/\s+/g, ': ');
asd = outputFile.Write(finalString.replace(/^(_)/, "") + ",\r\n");
}
}
outputFile.Write("};\r\n");
inputFile.Close();
outputFile.Close();
}

You can use substring in order to remove the last character of the string after you have formed the string:
finalString = finalString.substring(0, finalString.length - 1);
An alternative would be the use of slice, taking into consideration that negative indices are relative to the end of the string:
finalString = finalString.slice(0,-1);
Take a look in this question for more.
UPDATE: For your case, you could check whether or not you have reached the EOF - meaning you have read the last line, and then apply slice or substring:
//....
var stringReadPosition = readLine.substr(8);
var finalString = stringReadPosition.replace(/\s+/g, ': ');
//Check if stream reached EOF.
if(inputFile.AtEndOfStream) {
finalString = finalString.slice(0,-1);
}
asd = outputFile.Write(finalString.replace(/^(_)/, "") + ",\r\n");
//....

try this asd = asd.replace(/,\s*$/, "");
this will remove last comma, I have tried this, its working .Check if it works in ur code.
Try this code inside while loop

Regular expression to separate smileys from text

I am trying to create a regular expression in Javascript to separate any occurrence of :) from the surrounding text.
Given the following:
:)This is a line of text :) with several smileys in it :). So there.,:):)
I would like to get the resulting 8 groups:
:)
This is a line of text
:)
with several smileys in it
:)
. So there.,
:)
:)
At the moment I use ([^:)]+) which only groups the surrounding text without the smileys. What adjustment could I make so that the smileys are also grouped?

I'd suggest:
var str = ":)This is a line of text :) with several smileys in it :). So there.,:):)",
matches = str.split(/(\:\))/);
console.log(matches);​
JS Fiddle demo.
Added filtering to remove the empty matches from the above:
var str = ":)This is a line of text :) with several smileys in it :). So there.,:):)",
matches = str.split(/(\:\))/),
matched = [];
for (var i = 0, len = matches.length; i < len; i++) {
if (matches[i].length) {
matched.push(matches[i]);
}
}
console.log(matched);​
JS Fiddle demo.
A further version, with actual on-screen output:
var str = ":)This is a line of text :) with several smileys in it :). So there.,:):)",
matches = str.split(/(\:\))/),
matched = [], li,
list = document.createElement('ol');
document.body.appendChild(list);
for (var i = 0, len = matches.length; i < len; i++) {
if (matches[i].length) {
matched.push(matches[i]);
li = document.createElement('li');
txt = document.createTextNode(matches[i]);
li.appendChild(txt);
list.appendChild(li);
}
}
console.log(matched);​
JS Fiddle demo.

split:
var string = "Given the following: :)This is a line of text :) with several smileys in it :). So there.,:):)";
var groups = string.split(/:\)/);
This will return an array in which each element is a part of text without :).
Since the text has been split on each :), we can construct the result you want by adding a :) between each parts of text:
var parts = [groups[0]];
for (var i = 1; i < groups.length; ++i) {
parts.push(':)');
parts.push(groups[i]);
}
The result is this:
:)
This is a line of text
:)
with several smileys in it
:)
. So there.,
:)
:)
Try this here: http://jsfiddle.net/Gxr6U/3/
If you want to replace smilies by images, you could do this:
var frags = document.createDocumentFragment();
frags.appendChild(document.createTextNode(groups[0]));
for (var i = 1; i < groups.length; ++i) {
var img = document.createElement('img');
img.src='http://../smiley.png';
frags.push(img);
frags.appendChild(document.createTextNode(groups[i]));
}
If you just want to remove smilies:
var text = groups.join('');

The following will successfully group the string you mentioned as you want:
your_match = your_string.match(/(:\)|[^:)]*)/g)
However, like your original RegExp, you will encounter problems if a : or ) appears without being in a smiley. These characters will disappear from the match groups if not within a smiley.

You can use this pattern:
/:\)|(?:[^:]+|:(?!\)))+/g
This matches either :) or any character except : or a : that is not followed a ).