I'm writing a function to replace all occurrences of variables p and q with their respective values without using eval(), however, I'm running into some unexpected behaviors. BTW, I'm using phpjs for the str_replace
Fiddle: http://jsfiddle.net/5Uedt/2/
function table(str){
str=str_replace(["nand","nor","implies","equals","not","xor","and","or","(",")"],[" 3 "," 4 "," 5 "," 6 "," 7 "," 8 ", " 9 ", " 10 ", " ( "," ) "],str).replace(/\s{2,}/g, ' ').trim();
str=str_replace(["3","4","5","6","7","8", "9", "10", "(",")"],["nand","nor","implies","equals","not","xor","and","or","(",")"],str).split(" ");
var vars={p:1,q:1};
for(vars['p']=1;vars['p']>=0;vars['p']--){
for(vars['q']=1;vars['q']>=0;vars['q']--){
alert(str);
newinput=str;
for(var i=0;i<newinput.length;i++){
var token=newinput[i];
if(token.length===1){
console.log(newinput[i]);
newinput[i]=vars[newinput[i]];
}
}
// console.log(n.join(" "));
}
}
}
I have this code for replacing all occurrences, but it's not working. I'm alerting the original string entered in every time, however, the string changes. The expected output of the function is p,and,q repeated 4 times, instead, I have p,and,q, then 1,and,1 repeated 3 times. However, I don't seem to have any assignments to str. Does anyone know why this is happening?
When you set newinput equal to str, you're still referencing that original object. When you change the value later in newinput you affect the str variable.
If you want to clone the object you can iterate over the properties of str like so:
var newinput = {};
for(var key in str) {
newinput[key] = str[key];
}
Thus making a clone of your original object and you won't be affecting it's values. Assuming you don't have objects you want to clone inside your str object. If you do, just run this function recursively.
Updated Fiddle
Related
I have an object in JS like this:
var getToDoValue = document.getElementById("toDoInput").value;
var nameOfTeamMember = "Tobias";
var person = new Object();
person.task = "Task: " + getToDoValue;
person.member = "Member: " + nameOfTeamMember;
But problem comes when I try to enter the value of "nameOfTeamMember into an if statement:
var mem = person.member;
if (mem == "Tobias") {
console.log("works");
}
This does not work. But when I just console.log "var mem" outside of if statement it gives me "Member: Tobias". Any suggestions? Im still kinda new to JS so prob something with the comparisons
the issue with you code is that the value in person.member is "Member: Tobias" as you pointed out from the result of your console.log, which is the result from the line of code below where you are concatenating the name with the string "Memeber: " and assigning it to the member property.
person.member = "Member: " + nameOfTeamMember;
One option you could use to do the comparison would be:
if (mem.contains("Tobias", 8) {
console.log("works");
}
The 8 is so your search starts after the colon (:) so you don't include "Member:" in it, just what comes after it, which is the actual member name.
I have been testing ways to check individual characters in a string for a numeric value. I set up a for loop that goes through them, but when I'm logging it to the console, I get a weird response:
isNumeric: function(n){
for(var i = 0; i < n.length; i++){
console.log("Looping " + i+1);
}
},
So I passed in the value "10" to test it. I get a weird response when I call the function. I get two logs onto the console (like expected), but it says
Looping 01
Looping 11
What is going on here? I didn't think that I was concating strings here, but for some reason it thinks I am? I declared i as an integer var i = 0; and when you increment it by one, what is it doing?
The only other thing I think it must be doing is logging something else appended to Looping 0 and Looping 1, but I don't think that's the case.
If anyone can please help, this is really bugging me and I can't seem to fix it.
Thanks in advance.
+ is left-to-right associative. The expression is evaluated as
('Looping ' + i) + 1
Is it clearer now why string concatenation is performed? If any of the two operands of a + operation is a string, string concatenation is performed. 'Looping ' is a string, hence 'Looping ' + i results in a string.
To change precedence or associativity, you have to use the grouping "operator" ((...)).
You mean console.log("Looping " + (i+1));
The "1" is being appended as a string.
console.log("Looping " + i+1); is being parsed from left to right, as ("Looping " + i) + 1. Add parentheses in the right spot and it should work:
console.log("Looping " + (i+1));
You are concatenating strings, not adding numbers. First, the value of i is cast to a string and concatenated to Looping, resulting in Looping 0. Then, the number 1 is cast to a string and concatenated as well, resulting in what you are seeing: Looping 01.
To get the result you want, you can simply put the i+1 in parentheses.
console.log("Looping " + (i+1));
the problem lies in the line where you do the actual logging :
console.log("Looping " + i+1);
First "Looping " + i happens.
Because "Looping" is a string, i gets cast to a string and appended to "Looping".
The result :
"Looping 0"
Then, the 1 gets added the same way.
"Looping 01"
If you want to keep this from happening, use parenthesis like so :
isNumeric: function(n){
for(var i = 0; i < n.length; i++){
console.log("Looping " + (i+1));
}
},
They are right to add the parentheses, the whole code would be:
isNumeric: function(n){
for(var i = 0; i < n.length; i++){
console.log("Looping " + (i+1));
}
},
Compare your results with this:
n=[1,2,3,4]
function isnum(n){
for(var i = 0; i < n.length; i++){
console.log("Looping " + i+1);
console.log("Looping " + (i+1));
}
}
isnum(n);
This generates the output:
Looping 01
Looping 1
Looping 11
Looping 2
Looping 21
Looping 3
Looping 31
Looping 4
In the statement "Looping " + i+1 what's happening is that "Looping " + i is happening first, i being cast to a string value for the concatenation with "Looping ". The 1 is also being cast as a string value for concatentation. By putting parens around the i+1 we can force (i+1) to happen first as addition before being concatenated, so the output is what you would expect.
I am trying to edit a Greasemonkey/jQuery script. I can't post the link here.
The code is obfuscated and compressed with minify.
It starts like this:
var _0x21e9 = ["\x67\x65\x74\x4D\x6F\x6E\x74\x68", "\x67\x65\x74\x55\x54\x43\x44\x61\x74\x65", ...
After "decoding" it, I got this:
var _0x21e9=["getMonth","getUTCDate","getFullYear", ...
It is a huge list (500+ ). Then, it has some variables like this:
month = date[_0x21e9[0]](), day = date[_0x21e9[1]](), ...
_0x21e9[0] is getMonth, _0x21e9[1] is getUTCDate, etc.
Is it possible to replace the square brackets with the actual variable name? How?
I have little knowledge in javascript/jQuery and can not "read" the code the way it is right now.
I just want to use some functions from this huge script and remove the others I do not need.
Update: I tried using jsbeautifier.org as suggested here and in the duplicated question but nothing changed, except the "indent".
It did not replace the array variables with the decoded names.
For example:
jsbeautifier still gives: month = date[_0x21e9[0]]().
But I need: month = date["getMonth"]().
None of the online deobfuscators seem to do this, How can I?
Is there a way for me to share the code with someone, at least part of it? I read I can not post pastebin, or similar here. I can not post it the full code here.
Here is another part of the code:
$(_0x21e9[8] + vid)[_0x21e9[18]]();
[8] is "." and [18] is "remove". Manually replacing it gives a strange result.
I haven't seen any online deobfuscator that does this yet, but the principle is simple.
Construct a text filter that parses the "key" array and then replaces each instance that that array is referenced, with the appropriate array value.
For example, suppose you have a file, evil.js that looks like this (AFTER you have run it though jsbeautifier.org with the Detect packers and obfuscators? and the Unescape printable chars... options set):
var _0xf17f = ["(", ")", 'div', "createElement", "id", "log", "console"];
var _0x41dcx3 = eval(_0xf17f[0] + '{id: 3}' + _0xf17f[1]);
var _0x41dcx4 = document[_0xf17f[3]](_0xf17f[2]);
var _0x41dcx5 = _0x41dcx3[_0xf17f[4]];
window[_0xf17f[6]][_0xf17f[5]](_0x41dcx5);
In that case, the "key" variable would be _0xf17f and the "key" array would be ["(", ")", ...].
The filter process would look like this:
Extract the key name using text processing on the js file. Result: _0xf17f
Extract the string src of the key array. Result:
keyArrayStr = '["(", ")", \'div\', "createElement", "id", "log", "console"]';
In javascript, we can then use .replace() to parse the rest of the JS src. Like so:
var keyArrayStr = '["(", ")", \'div\', "createElement", "id", "log", "console"]';
var restOfSrc = "var _0x41dcx3 = eval(_0xf17f[0] + '{id: 3}' + _0xf17f[1]);\n"
+ "var _0x41dcx4 = document[_0xf17f[3]](_0xf17f[2]);\n"
+ "var _0x41dcx5 = _0x41dcx3[_0xf17f[4]];\n"
+ "window[_0xf17f[6]][_0xf17f[5]](_0x41dcx5);\n"
;
var keyArray = eval (keyArrayStr);
//-- Note that `_0xf17f` is the key name we already determined.
var keyRegExp = /_0xf17f\s*\[\s*(\d+)\s*\]/g;
var deObsTxt = restOfSrc.replace (keyRegExp, function (matchStr, p1Str) {
return '"' + keyArray[ parseInt(p1Str, 10) ] + '"';
} );
console.log (deObsTxt);
if you run that code, you get:
var _0x41dcx3 = eval("(" + '{id: 3}' + ")");
var _0x41dcx4 = document["createElement"]("div");
var _0x41dcx5 = _0x41dcx3["id"];
window["console"]["log"](_0x41dcx5);
-- which is a bit easier to read/understand.
I've also created an online page that takes JS source and does all 3 remapping steps in a slightly more automated and robust manner. You can see it at:
jsbin.com/hazevo
(Note that that tool expects the source to start with the "key" variable declaration, like your code samples do)
#Brock Adams solution is brilliant, but there is a small bug: it doesn't take into account simple quoted vars.
Example:
var _0xbd34 = ["hello ", '"my" world'];
(function($) {
alert(_0xbd34[0] + _0xbd34[1])
});
If you try to decipher this example, it will result on this:
alert("hello " + ""my" world")
To resolve this, just edit the replacedSrc.replace into #Brock code:
replacedSrc = replacedSrc.replace (nameRegex, function (matchStr, p1Str) {
var quote = keyArry[parseInt (p1Str, 10)].indexOf('"')==-1? '"' : "'";
return quote + keyArry[ parseInt (p1Str, 10) ] + quote;
} );
Here you have a patched version.
for (var i = 0; i < _0x21e9.length; i++) {
var funcName = _0x21e9[i];
_0x21e9[funcName] = funcName;
}
this will add all the function names as keys to the array. allowing you to do
date[_0x21e9["getMonth"]]()
I'm trying to use JavaScript to insert HTML ruby characters on my text. The idea is to find the kanji and replace it with the ruby character that is stored on the fgana array. My code goes like this:
for (var i = 0; i < kanji.length; i++) {
phrase = phrase.replace(kanji[i],"<ruby><rb>" + kanji[i] + "</rb><rt>" + fgana[i] + "</rt></ruby>");
}
It does that just fine when there aren't duplicated characters to be replaced, but when there are the result is different from what I except. For example, if the arrays are like this:
kanji = ["毎朝","時","時"]
fgana = ["まいあさ"、"とき"、"じ"]
And the phrase is あの時毎朝６時におきていた the result becomes:
あの<ruby><rb><ruby><rb>時</rb><rt>じ</rt></ruby></rb><rt>とき</rt></ruby><ruby><rb>毎朝</rb><rt>まいあさ</rt></ruby> 6 時 におきていた。
Instead of the desired:
あの<ruby><rb>時</rb><rt>とき</rt></ruby><ruby><rb>毎朝</rb><rt>まいあさ</rt></ruby> 6 <ruby><rb>時</rb></ruby></rb><rt>じ</rt> におきていた。
To illustrate it better, look at the rendered example:
Look at how the first 時 receives both values とき and じ while the second receives nothing. The idea is to the first be とき and the second じ (as Japanese has different readings for the same character depending on some factors).
Whats might be the failure on my code?
Thanks in advance
It fails because the char you are looking for still exists in the replaced version:
...replace(kanji[i],"<ruby><rb>" + kanji[i]...
And this one should work:
var kanji = ["毎朝", "時", "時"],
fgana = ["まいあさ", "とき", "じ"],
phrase = "あの時毎朝 6 時におきていた",
rx = new RegExp("(" + kanji.join("|") + ")", "g");
console.log(phrase.replace(rx, function (m) {
var pos = kanji.indexOf(m),
k = kanji[pos],
f = fgana[pos];
delete kanji[pos];
delete fgana[pos];
return "<ruby><rb>" + k + "</rb><rt>" + f + "</rt></ruby>"
}));
Just copy and paste into console and you get:
あの<ruby><rb>時</rb><rt>とき</rt></ruby><ruby><rb>毎朝</rb><rt>まいあさ</rt></ruby> 6 <ruby><rb>時</rb><rt>じ</rt></ruby>におきていた
Above line is a bit different from your desired result thou, just not sure if you indeed want this:
...6 <ruby><rb>時</rb></ruby></rb><rt>じ</rt>...
^^^^^ here ^ not here?
I've started javascript just today and done my research about this matter around the web. But I couldn't get the hang of the usage of closures, especially for this code I've written:
function writeit()
{
var tbox = document.getElementById('a_tbox').value;
var letters = tbox.split("");
for(var i=0;i<letters.length;i++)
{
if(letters[i]==="a")
{
document.a_form.b_tbox.value = i+1 + ". character is a";
}
else if(letters[i]==="b")
{
document.a_form.b_tbox.value = i+1 + ". character is b";
}
else
{
document.a_form.b_tbox.value = i+1 + ". character is not a nor b";
}
}
}
As you see here, I'd like to get a string from a text box, split it to an array and change the values inside it by using a for loop. What I expect from my code is, if the text box contained "abc" as a user contribution, the output would be "1. value is a 2. value is b 3. value is not a nor b". But it only gives "3. value is not a nor b" as an output. What can be done to prevent this problem?
Each iteration of your loop is overriding the last result since you are replacing the value of the textbox rather than adding on for each iteration. Use += to avoid this, like so:
document.a_form.b_tbox.value += i+1 + ". character is not a nor b";