Transform a string into array using javascript - javascript

I have a string like this:
string = "locations[0][street]=street&locations[0][street_no]=
34&locations[1][street]=AnotherStreet&locations[1][street_no]=43";
What must I do with this string so i can play with locations[][] as I wish?

You could write a parser:
var myStr = "locations[0][street]=street&locations[0][street_no]=34&locations[1][street]=AnotherStreet&locations[1][street_no]=43";
function parseArray(str) {
var arr = new Array();
var tmp = myStr.split('&');
var lastIdx;
for (var i = 0; i < tmp.length; i++) {
var parts = tmp[i].split('=');
var m = parts[0].match(/\[[\w]+\]/g);
var idx = m[0].substring(1, m[0].length - 1);
var key = m[1].substring(1, m[1].length - 1);
if (lastIdx != idx) {
lastIdx = idx;
arr.push({});
}
arr[idx * 1][key] = parts[1];
}
return arr;
}
var myArr = parseArray(myStr);

As Shadow wizard said, using split and eval seems to be the solution.
You need to initialize locations first, if you want to avoid an error.
stringArray=string.split("&");
for (var i=0;i<stringArray.length;i++){
eval(stringArray[i]);
}
However, you might need to pay attention to what street and street_no are.
As is, it will produce an error because street is not defined.
Edit: and you'll need to fully initialize locations with as many item as you'll have to avoid an error.

Related

Return multiple strings from function based on variable number

I have a string
var str = 'string'
I have a multiplier
var mult = 3
I want to return stringstringstring
The mult will change. Basically mult is kind of like a power but this is a string not a number. And I need to return multiple strings. I'm thinking of looping where mult = the number of times to loop and each would conceptually 'push' but I don't want an array or something like =+ but not a number. I'm thinking I could have the output push to an array the number of times = to mult, and then join the array - but I don't know if join is possible without a delimiter. I'm new at javascript and the below doesn't work but it's what I'm thinking. There's also no ability to input a function in the place I'm running javascript and also no libraries.
var loop = {
var str = 'string'
var arr = [];
var mult = 3;
var i = 0
for (i = 0, mult-1, i++) {
arr.push('string'[i]);
}
}
var finalString = arr.join(''); // I don't know how to get it out of an object first before joining
Not sure if what I want is ridiculous or if it's at all possible
You mean something like below,
var str = 'string'
var mult = 3
var str2 = ''
for(i = 0; i < mult; i++) {
str2 += str
}
console.log(str2)
var str = 'string'
var mult = 3;
var sol =""
while(mult--) {
sol +=str;
}
console.log(sol)
Using resusable function:
const concatStr= (str, mult)=>{
var sol =""
while(mult--) {
sol +=str;
}
console.log(sol)
}
concatStr("string",3)
Using the inbuilt Array.from method:
var str = "string"
var mult = 3
var sol = Array.from({length: mult}, ()=> str).join("")
console.log(sol)
function concatString(str, mult) {
var result = ''
for(i = 0; i < mult; i++) {
result = result.concat(str);
}
return result;
}
const value = concatString('string', 3);
console.log(value);
Also you can use array inbuilt methods,
const mult = 3, displayVal = 'str';
Array(mult).fill(displayVal).join('');
// the string object has a repeat method
console.log('string'.repeat(3));

Javascript global string replace with different elements from array?

I'm a Javascript noob using regex in javascript to globally replace text on web page. Easy enough.
v = v.replace(/\Simon\b/g, "JS Noob");
I know I can replace with functions, but I can't get this to work:
v = v.replace(/\bSimon\b/g, function(replaceLoop) {
var myStringArray = ["herp","derp","clueless","hurrrrr"];
var arrayLength = myStringArray.length;
for (var i = 0; i < arrayLength; i++){
replaceLoop = myStringArray;
return replaceLoop;
}
}
I have a feeling I'm thinking about this all wrong.
Step 1, make a function which returns the next item from an Array each time
function iterGen(arr, i) {
i || (i = 0);
return function () {
i %= arr.length;
return arr[i++];
};
}
Step 2, pass this into your replace
v = v.replace(/\bSimon\b/g, iterGen(["herp","derp","clueless","hurrrrr"]));
A quick syntax error is causing issues, you are missing the closing ); to .replace(). Also, you are setting replaceLoop = myStringArray instead of a specific string. Assuming you want a random index, you'll need Math.random().
v = v.replace(/\bSimon\b/g, function(replaceLoop) {
var myStringArray = ["herp","derp","clueless","hurrrrr"];
var arrayLength = myStringArray.length;
var index = Math.floor(Math.random() * arrayLength);
return myStringArray[index];
});

Find min and max value in csv file

Looking to extend my javascript object, I want to find the minium and maximum of a multicolumn csvfile. I have looked up solutions but I cannot really grasp the right way. I found a solution here: Min and max in multidimensional array but I do not get an output.
My code that I have for now is here:
function import(filename)
{
var f = new File(filename);
var csv = [];
var x = 0;
if (f.open) {
var str = f.readline(); //Skips first line.
while (f.position < f.eof) {
var str = f.readline();
csv.push(str);
}
f.close();
} else {
error("couldn't find the file ("+ filename +")\n");
}
for (var i=(csv.length-1); i>=0; i--) {
var str = csv.join("\n");
var a = csv[i].split(","); // convert strings to array (elements are delimited by a coma)
var date = Date.parse(a[0]);
var newdate = parseFloat(date);
var open = parseFloat(a[1]);
var high = parseFloat(a[2]);
var low = parseFloat(a[3]);
var close = parseFloat(a[4]);
var volume = parseFloat(a[5]);
var volume1000 = volume /= 1000;
var adjusted_close = parseFloat(a[6]);
outlet(0, x++, newdate,open,high,low,close,volume1000,adjusted_close); // store in the coll
}
}
Edit
What if, instead of an array of arrays, you use an array of objects? This assumes you're using underscore.
var outlet=[];
var outletkeys=['newdate','open','high','low','close','volume','volume1000','adjusted_close'];
for (var i=(csv.length-1);i>0; i--) {
var a = csv[i].split(",");
var date = Date.parse(a[0]);
var volume = parseFloat(a[5],10);
outlet.push( _.object(outletkeys, [parseFloat(date,10) , parseFloat(a[1],10) , parseFloat(a[2],10) , parseFloat(a[3],10) , parseFloat(a[4],10) , parseFloat(a[5],10) , volume /= 1000 , parseFloat(a[6],10) ]) );
}
Then the array of the column 'open' would be
_.pluck(outlet,'open');
And the minimum it
_.min(_.pluck(outlet,'open'));
Edit2
Let's forget about underscore for now. I believe you need to get the maximum value on the second column, which is what you put in your open variable.
¿Would it help if you could have that value right after the for loop? For example
var maxopen=0;
for (var i=(csv.length-1); i>=0; i--) {
var a = csv[i].split(",");
var date = Date.parse(a[0]);
var newdate = parseFloat(date);
var open = parseFloat(a[1]);
maxopen=(open>maxopen)? open : maxopen; // open overwrites the max if it greater
...
...
outlet(0, x++, newdate,open,high,low,close,volume1000,adjusted_close);
}
console.log('Maximum of open is',maxopen);

Javascript pull data from string?

I have a long URL that contains some data that I need to pull. I am able to get the end of the URL by doing this:
var data = window.location.hash;
When I do alert(data); I receive a long string like this:
#access_token=0u2389ruq892hqjru3h289r3u892ru3892r32235423&token_type=Bearer&expires_in=3600
note in the example the access token is not valid, just random numbers I input for example purpose
Now that I have that long string stored in a variable, how can I parse out just the access token value, so everything in between the first '=' and '&. So this is what I need out of the string:
0u2389ruq892hqjru3h289r3u892ru3892r32235423
I was reading up on php explode, and others java script specific stuff like strip but couldn't get them to function as needed. Thanks guys.
DEMO (look in your debug console)
You will want to split the string by the token '&' first to get your key/value pairs:
var kvpairs = document.location.hash.substring(1).split('&');
Then, you will want to split each kvpair into a key and a value:
for (var i = 0; i < kvpairs.length; i++) {
var kvpair = kvpairs[i].split('=');
var k = kvpair[0];
var v = kvpair[1];
if (k != 'access_token')
continue;
console.log(v); //Here's your access token.
}
Here is a version wrapped into a function that you can use easily:
function getParam(hash, key) {
var kvpairs = hash.substring(1).split('&');
for (var i = 0; i < kvpairs.length; i++) {
var kvpair = kvpairs[i].split('=');
var k = kvpair[0];
var v = kvpair[1];
if (k != key)
continue;
return v;
}
return null;
}
Usage:
getParam(document.location.hash, 'access_token');
data.split("&")[0].split("=")[1]
var str = "#access_token=0u2389ruq892hqjru3h289r3u892ru3892r32235423&token_type=Bearer&expires_in=3600";
var requiredValue = str.split('&')[0].split('=')[1];
I'd use regex in case value=key pair changes position
var data = "#token_type=Bearer&access_token=0u2389ruq892hqjru3h289r3u892ru3892r32235423&expires_in=3600";
RegExp("access_token=([A-Za-z0-9]*)&").exec(data)[1];
output
"0u2389ruq892hqjru3h289r3u892ru3892r32235423"
Looks like I'm a bit late on this. Here's my attempt at a version that parses URL parameters into a map and gets any param by name.
var str = "#access_token=0u2389ruq892hqjru3h289r3u892ru3892r32235423&token_type=Bearer&expires_in=3600";
function urlToMap(url){
var startIndex = Math.max(url.lastIndexOf("#"), url.lastIndexOf("?"));
url = url.substr(startIndex+1);
var result = {};
url.split("&").forEach(function(pair){
var x = pair.split("=");
result[x[0]]=x[1];
});
return result;
}
function getParam(url, name){
return urlToMap(url)[name];
}
console.log(getParam(str, "access_token"));
To answer to your question directly (what's between this and that), you would need to use indexOf and substring functions.
Here's a little piece of code for you.
function whatsBetween (_strToSearch, _leftText, _rightText) {
var leftPos = _strToSearch.indexOf(_leftText) + _leftText.length;
var rightPos = _strToSearch.indexOf(_rightText, leftPos);
if (leftPos >= 0 && leftPos < rightPos)
return _strToSearch.substring(leftPos, rightPos);
return "";
}
Usage:
alert(whatsBetween, data,"=","#");
That said, I'd rather go with a function like crush's...
try this
var data = window.location.hash;
var d1 = Array();
d1 = data.split("&")
var myFilteredData = Array();
for( var i=0;i<d1.length;i++ )
{
var d2 = d1[i].split("=");
myFilteredData.push(d2[1]); //Taking String after '='
}
I hope it helps you.

Javascript string manipulation url

My problem is I am trying to extract certain things from the url. I am currently using
window.location.href.substr()
to grab something like "/localhost:123/list/chart=2/view=1"
What i have now, is using the index positioning to grab the chart and view value.
var chart = window.location.href.substr(-8);
var view = window.location.href.substr(-1);
But the problem comes in with I have 10 or more charts. The positioning is messed up. Is there a way where you can ask the code to get the string between "chart=" and the closest "/"?
var str = "/localhost:123/list/chart=2/view=1";
var data = str.match(/\/chart=([0-9]+)\/view=([0-9]+)/);
var chart = data[1];
var view = data[2];
Of course you may want to add in some validation checks before using the outcome of the match.
Inspired by Paul S. I have written a function version of my answer:
function getPathVal(name)
{
var path = window.location.pathname;
var regx = new RegExp('(?:/|&|\\?)'+name+'='+'([^/&,]+)');
var data = path.match(regx);
return data[1] || null;
}
getPathVal('chart');//2
Function should work for fetching params from standard get parameter syntax in a URI, or the syntax in your example URI
Here's a way using String.prototype.indexOf
function getPathVar(key) {
var str = window.location.pathname,
i = str.indexOf('/' + key + '=') + key.length + 2,
j = str.indexOf('/', i);
if (i === key.length + 1) return '';
return str.slice(i, j);
}
// assuming current path as described in question
getPathVar('chart');
You could split your string up, with "/" as delimiter and then loop through the resulting array to find the desired parameters. That way you can easily extract all parameters automatically:
var x = "/localhost:123/list/chart=2/view=1";
var res = {};
var spl = x.split("/");
for (var i = 0; i < spl.length; i++) {
var part = spl[i];
var index = part.indexOf("=");
if (index > 0) {
res[part.substring(0, index)] = part.substring(index + 1);
}
}
console.log(res);
// res = { chart: 2, view: 1}
FIDDLE

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