Develop Reference

convert String to array in javascript "datastatusMonthly[0]"

datastatusMonthly[0] - This is my String in javascript
If i print this, it is printing as same string.
How do i get the value of '0' index in array datastatusMonthly using this above string?
Any help please?

You can use eval. The eval function will evaluate your string. JS bin here https://jsbin.com/guqoqukoqa/edit?js,console

Solution without eval, which is evil, using regex with group:
var datastatusMonthly = [3];
var text = 'datastatusMonthly[0]';
var regex = /(datastatusMonthly)\[([0-9]+)\]/g;
var match = regex.exec(text);
var arrayName = match[1];
var arrayIndex = match[2];
console.log(window[arrayName][arrayIndex]);

This dose't have to be in a String i guess. correct me if i am not understanding it properly
var fistElement = datastatusMonthly[0];
This link might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array#Accessing_array_elements

Regex append characters to a substring

My string comes in two flavours-
var a = /aid/f82eb514073124cd10d468b74eee5663?sg=1#/propertyinfo
or
var a = /aid/f82eb514073124cd10d468b74eee5663#/propertyinfo
I want to append the content that comes after aid/ and before ? or # with "-test". In either of the above scenarios the result would be f82eb514073124cd10d468b74eee5663-test
hence
a = /aid/f82eb514073124cd10d468b74eee5663-test#/propertyinfo
or
a = = /aid/f82eb514073124cd10d468b74eee5663-test?sg=1#/propertyinfo

Seems like you're looking for something like this.
Regular expression /\/aid\/[0-9A-F]*/i and replacement expression $0-test.
JavaScript is a little bit different than just plain regular expression antics, so here you go;
var a = "/aid/f82eb514073124cd10d468b74eee5663?sg=1#/propertyinfo";
alert(a.replace(/(\/aid\/[0-9A-F]*)/i, "$1-test"));

given your examples I guess that string after /aid/ is some kind of md5 hash
this should work for you:
'/aid/f82eb514073124cd10d468b74eee5663#/propertyinfo'.replace(new RegExp('/aid/([a-f0-9]{32})'), '$1-test');
if you don't want to be that much specific about length, you can try the following:
'/aid/f82eb514073124cd10d468b74eee5663#/propertyinfo'.replace(new RegExp('/aid/([a-f0-9]+)'), '$1-test');

Simple solution using String.replace function:
var a = '/aid/f82eb514073124cd10d468b74eee5663sg=1#/propertyinfo',
result = a.replace(/aid\/([^?#]+)(?=\?|#)/, "aid/$1-test");
console.log(result); // /aid/f82eb514073124cd10d468b74eee5663-test?sg=1#/propertyinfo

I suggest replacing directly the # or ? so the regex is nice and simple. :)
var a = "/aid/f82eb514073124cd10d468b74eee5663?sg=1#/propertyinfo";
var b = "/aid/f82eb514073124cd10d468b74eee5663#/propertyinfo";
console.log(a.replace(/([\?#])/,"-test$1"));
console.log(b.replace(/([\?#])/,"-test$1"));

var a = '/aid/f82eb514073124cd10d468b74eee5663?sg=1#/propertyinfo';
a.replace(/(\/aid\/.+)(\?sg=1)(#\/propertyinfo)/,function(text,c,d,e){
return c+'-test'+e;
})
//Output: "/aid/f82eb514073124cd10d468b74eee5663-test#/propertyinfo"
a.replace(/(\/aid\/.+)(\?sg=1#\/propertyinfo)/,function(text,c,d){
return c+'-test'+d;
});
//Output: "/aid/f82eb514073124cd10d468b74eee5663-test?sg=1#/propertyinfo"

How to remove the last matched regex pattern in javascript

I have a text which goes like this...
var string = '~a=123~b=234~c=345~b=456'
I need to extract the string such that it splits into
['~a=123~b=234~c=345','']
That is, I need to split the string with /b=.*/ pattern but it should match the last found pattern. How to achieve this using RegEx?
Note: The numbers present after the equal is randomly generated.
Edit:
The above one was just an example. I did not make the question clear I guess.
Generalized String being...
<word1>=<random_alphanumeric_word>~<word2>=<random_alphanumeric_word>..~..~..<word2>=<random_alphanumeric_word>
All have random length and all wordi are alphabets, the whole string length is not fixed. the only text known would be <word2>. Hence I needed RegEx for it and pattern being /<word2>=.*/

This doesn't sound like a job for regexen considering that you want to extract a specific piece. Instead, you can just use lastIndexOf to split the string in two:
var lio = str.lastIndexOf('b=');
var arr = [];
var arr[0] = str.substr(0, lio);
var arr[1] = str.substr(lio);
http://jsfiddle.net/NJn6j/

I don't think I'd personally use a regex for this type of problem, but you can extract the last option pair with a regex like this:
var str = '~a=123~b=234~c=345~b=456';
var matches = str.match(/^(.*)~([^=]+=[^=]+)$/);
// matches[1] = "~a=123~b=234~c=345"
// matches[2] = "b=456"
Demo: http://jsfiddle.net/jfriend00/SGMRC/

Assuming the format is (~, alphanumeric name, =, and numbers) repeated arbitrary number of times. The most important assumption here is that ~ appear once for each name-value pair, and it doesn't appear in the name.
You can remove the last token by a simple replacement:
str.replace(/(.*)~.*/, '$1')
This works by using the greedy property of * to force it to match the last ~ in the input.
This can also be achieved with lastIndexOf, since you only need to know the index of the last ~:
str.substring(0, (str.lastIndexOf('~') + 1 || str.length() + 1) - 1)
(Well, I don't know if the code above is good JS or not... I would rather write in a few lines. The above is just for showing one-liner solution).

A RegExp that will give a result that you may could use is:
string.match(/[a-z]*?=(.*?((?=~)|$))/gi);
// ["a=123", "b=234", "c=345", "b=456"]
But in your case the simplest solution is to split the string before extract the content:
var results = string.split('~'); // ["", "a=123", "b=234", "c=345", "b=456"]
Now will be easy to extract the key and result to add to an object:
var myObj = {};
results.forEach(function (item) {
if(item) {
var r = item.split('=');
if (!myObj[r[0]]) {
myObj[r[0]] = [r[1]];
} else {
myObj[r[0]].push(r[1]);
}
}
});
console.log(myObj);
Object:
a: ["123"]
b: ["234", "456"]
c: ["345"]

(?=.*(~b=[^~]*))\1
will get it done in one match, but if there are duplicate entries it will go to the first. Performance also isn't great and if you string.replace it will destroy all duplicates. It would pass your example, but against '~a=123~b=234~c=345~b=234' it would go to the first 'b=234'.
.*(~b=[^~]*)
will run a lot faster, but it requires another step because the match comes out in a group:
var re = /.*(~b=[^~]*)/.exec(string);
var result = re[1]; //~b=234
var array = string.split(re[1]);
This method will also have the with exact duplicates. Another option is:
var regex = /.*(~b=[^~]*)/g;
var re = regex.exec(string);
var result = re[1];
// if you want an array from either side of the string:
var array = [string.slice(0, regex.lastIndex - re[1].length - 1), string.slice(regex.lastIndex, string.length)];
This actually finds the exact location of the last match and removes it regex.lastIndex - re[1].length - 1 is my guess for the index to remove the ellipsis from the leading side, but I didn't test it so it might be off by 1.

how to get id from string which ends with certain word (regexp)

i want to get id which is ends with "_theTable" in string using regex. but i am not getting that . i am using this code:-
var str="<table id='dnn_ctl_123_theTable'><tr><td></td></tr></table>";
var rexexp = new RegExp("\b\w*_theTable\b");
var matchedwrd=rexexp.exec(str);
Please guide how to do this?
Thanks in Advance

When you use a new Regexp you have to escape your backslashes like so:
var rexexp = new RegExp("\\b\\w*_theTable\\b");
Or you can use a regex literal:
var rexexp = /\b\w*_theTable\b/;

var str="<table id='dnn_ctl_123_theTable'><tr><td></td></tr></table>"
var rexexp = /id='(.+?)_theTable'/;
var matchedwrd=rexexp.exec(str);
alert(matchedwrd[1]);

var str="<table id='dnn_ctl_123_theTable'><tr id='another'><td></td></tr></table>";
var regEx = /id='(.*?_theTable)'/;
var id = str.match(regEx)[1];
document.write(id);
​

I'd probably use the pattern id='([^']*)_theTable' for this. Then $1 should correspond to the portion of the id before _theTable. If you want to include the _theTable bit, just move the closing parenthesis after it.

jQuery - trim the variable

I have following example:
var VarFull = $('#selectror').attr('href') where .attr('href') = "#tabs1-1"
How can I trim that to "tabs1-1" ( without #)??
Any suggestions much appreciated.

Use substring:
var VarFull = $('#selectror').attr('href').substring(1);

You can use JavaScript's string replace(): https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/String/replace
var VarFull = $('#selectror').attr('href');
var trimmed = VarFull.replace('#','');
Edit:
This is a good article on JS string manipulation: http://www.quirksmode.org/js/strings.html

You could use replace -
var VarFull = $('#selectror').attr('href').replace('#','');

try this regEx with replace-
var VarFull = $('#selectror').attr('href').replace(/\#*/g, "");
it will replace all the # in your attr.

If it's certain that the url will contain # anyway, you can even split and take second element of array.
var trimmed=$('#selectror').attr('href').split("#")[1]
But don't use this if URL may not contain # otherwise you'll get an undefined error for trying to get index 1 of the array by split().

For example: ". / email#gmail.com, / . \"
Now trim characters at the beginning and end of the string:
email_new = email.replace(/\W+$/g, '').replace(/^\W+/g, ''); // output : email#gmail.com