I'm new in StackOverflow and not sure whether I should ask this question here or not, so if I'm asking this question at wrong place, please let me know.
I want to implement dataSource in javascript (like ASP.NET). So I have created a jQuery plugin with these functions:
$.getUniqueString = function (prefix) {
if (!prefix) prefix = "s";
for (var loopIndex = 0; true; loopIndex++) {
if (typeof window[prefix + loopIndex] != "undefined") { // if sourceId exists
continue;
}
prefix = prefix + loopIndex;
break;
}
return prefix;
}
$.fn.dataSource = function (source) {
var sourceId;
if (!source) {
sourceId = $(this).attr("data-source-id");
return window[sourceId];
}
sourceId = $.getUniqueString();
$(this).attr("data-source-id", sourceId);
window[sourceId] = source;
}
This plugin works fine. And till now, I have not faced any difficulty. Here is the link to a working example (fiddle): http://jsfiddle.net/Gu2KQ/
But, my questions are:
Is my code safe enough for the client browser not to crash?
Any suggestion to optimize this code more?
Any other option to implement the same functionality better?
Any help would be appreciated.
Eval is unnecessary here. You can get and set global variables as properties of the window object.
$.getUniqueString = function (prefix) {
if (!prefix) prefix = "s";
for (var loopIndex = 0; true; loopIndex++) {
if (typeof window[prefix + loopIndex] != "undefined") { // if sourceId exists
continue;
}
prefix = prefix + loopIndex;
break;
}
return prefix;
}
$.fn.dataSource = function (source) {
var sourceId;
if (!source) {
sourceId = $(this).attr("data-source-id");
return window[sourceId];
}
sourceId = $.getUniqueString();
$(this).attr("data-source-id", sourceId);
window[sourceId] = source;
}
Related
I have built this function to replace a group of characters in a string by a random value from another list within a function:
function replaceExpr(a) {
var expToReplace = 0
var newSent = a
while (expToReplace == 0) {
if (a.search("zx") == -1) {
expToReplace = 1
} else {
var startPos = a.search("zx");
startPos += 2;
var endPos = a.search("xz");
var b = a.substring(startPos, endPos);
var fn = window[b];
if (typeof fn === "function") var newWord = fn();
final = newSent.replace("zx" + b + "xz", newWord);
newSent = final
a = a.replace("zx" + b + "xz", "")
}
}
return final
}
function appearance() {
var list = [
"attractive",
"fit",
"handsome",
"plain",
"short",
"tall",
"skinny",
"well-built",
"unkempt",
"unattractive"
]
return list[Math.floor(Math.random() * list.length)];
}
function personality() {
var list = [
"aggresive",
"absent-minded",
"cautious",
"detached from the real world",
"easygoing",
"focused",
"honest",
"dishonest",
"polite",
"uncivilized"
]
return list[Math.floor(Math.random() * list.length)];
}
An example :
var a = replaceExpr("Theodor is a zxappearancexz man. He seems rather zxpersonalityxz.")
alert(a)
// Theodor is a unattractive man. He seems rather cautious.
Everything works perfectly with the function but I have an issue related to it. As you can see, there's one grammar mistake : it's written "a unattractive" where it should be "an unattractive".
There's a function I usually use to to fix the a\an issue which is :
var AvsAnSimple = (function (root) {
//by Eamon Nerbonne (from http://home.nerbonne.org/A-vs-An), Apache 2.0 license
// finds if a word needs a "a" or "an" before it
var dict = "2h.#2.a;i;&1.N;*4.a;e;i;o;/9.a;e;h1.o.i;l1./;n1.o.o;r1.e.s1./;01.8;12.1a;01.0;12.8;9;2.31.7;4.5.6.7.8.9.8a;0a.0;1;2;3;4;5;6;7;8;9;11; .22; .–.31; .42; .–.55; .,.h.k.m.62; .k.72; .–.82; .,.92; .–.8;<2.m1.d;o;=1.=1.E;#;A6;A1;A1.S;i1;r1;o.m1;a1;r1; .n1;d1;a1;l1;u1;c1.i1.a1.n;s1;t1;u1;r1;i1;a1;s.t1;h1;l1;e1;t1;e1.s;B2.h2.a1.i1;r1;a.á;o1.r1.d1. ;C3.a1.i1.s1.s.h4.a2.i1.s1;e.o1.i;l1.á;r1.o1.í;u2.i;r1.r1.a;o1.n1.g1.j;D7.a1.o1.q;i2.n1.a1.s;o1.t;u1.a1.l1.c;á1. ;ò;ù;ư;E7;U1;R.b1;o1;l1;i.m1;p1;e1;z.n1;a1;m.s1;p5.a1.c;e;h;o;r;u1.l1;o.w1;i.F11. ;,;.;/;0;1;2;3;4;5;6;71.0.8;9;Ae;B.C.D.F.I2.L.R.K.L.M.N.P.Q.R.S.T.B;C1;M.D;E2.C;I;F1;r.H;I3.A1;T.R1. ;U;J;L3.C;N;P;M;O1. ;P1;..R2.A1. ;S;S;T1;S.U2.,;.;X;Y1;V.c;f1.o.h;σ;G7.e1.r1.n1.e;h1.a3.e;i;o;i1.a1.n1.g;o2.f1. ;t1.t1. ;r1.i1.a;w1.a1.r1.r;ú;Hs. ;&;,;.2;A.I.1;2;3;5;7;B1;P.C;D;F;G;H1;I.I6;C.G.N.P.S1.D;T.K1.9;L;M1;..N;O2. ;V;P;R1;T.S1.F.T;V;e2.i1.r;r1.r1.n;o2.n6;d.e1.s;g.k.o2;l.r1;i1.f;v.u1.r;I3;I2;*.I.n1;d1;e1;p1;e1;n1;d2;e1;n1;c1;i.ê.s1;l1;a1;n1;d1;s.J1.i1.a1.o;Ly. ;,;.;1;2;3;4;8;A3. ;P;X;B;C;D;E2. ;D;F1;T.G;H1.D.I1.R;L;M;N;P;R;S1;m.T;U1. ;V1;C.W1.T;Z;^;a1.o1.i1.g;o1.c1.h1.a1;b.p;u1.s1.h1;o.ộ;M15. ;&;,;.1;A1;.1;S./;1;2;3;4;5;6;7;8;Ai;B.C.D.F.G.J.L.M.N.P.R.S.T.V.W.X.Y.Z.B1;S1;T.C;D;E3.P1;S.W;n;F;G;H;I4. ;5;6;T1;M.K;L;M;N;O1.U;P;Q;R;S;T1;R.U2. ;V;V;X;b1.u1.m;f;h;o2.D1.e.U1;..p1.3;s1.c;Ny. ;+;.1.E.4;7;8;:;A3.A1;F.I;S1.L;B;C;D;E3.A;H;S1. ;F1;U.G;H;I7.C.D1. ;K.L.N.O.S.K;L;M1;M.N2.R;T;P1.O1.V1./1.B;R2;J.T.S1;W.T1;L1.D.U1.S;V;W2.A;O1.H;X;Y3.C1.L;P;U;a1.s1.a1.n;t1.h;v;²;×;O5;N1;E.l1;v.n2;c1.e.e1.i;o1;p.u1;i.P1.h2.i1.a;o2.b2;i.o.i;Q1.i1.n1.g1.x;Rz. ;&;,;.1;J./;1;4;6;A3. ;.;F1;T.B1;R.C;D;E3. ;S1.P;U;F;G;H1.S;I2.A;C1. ;J;K;L1;P.M5;1.2.3.5.6.N;O2.H;T2;A.O.P;Q;R1;F.S4;,...?.T.T;U4;B.M.N.S.V;X;c;f1;M1...h2.A;B;ò;S11. ;&;,;.4.E;M;O;T1..3.B;D;M;1;3;4;5;6;8;9;A3. ;8;S2;E.I.B;C3.A1. ;R2.A.U.T;D;E6. ;5;C3;A.O.R.I1.F.O;U;F3;&.H.O1.S.G1;D.H3.2;3;L;I2. ;S1.O.K2.I.Y.L3;A2. ;.;I1. ;O.M3;A1. ;I.U1.R.N5.A.C3.A.B.C.E.F.O.O5. ;A1.I;E;S1;U.V;P7;A7;A.C.D.M.N.R.S.E1. ;I4;C.D.N.R.L1;O.O.U.Y.Q1. ;R;S1;W.T9.A1. ;C;D;F;I;L;M;S;V;U7.B.L.M.N.P.R.S.V;W1.R;X1.M;h1.i1.g1.a1.o;p1.i1.o1;n.t2.B;i1.c1.i;T4.a2.i2.g1.a.s1.c;v1.e1.s;e1.a1.m1.p;u1.i2.l;r;à;Um..1.N1..1.C;/1.1;11. .21.1;L1.T;M1.N;N4.C1.L;D2. .P.K;R1. .a;b2;a.i.d;g1.l;i1.g.l2;i.y.m;no. ;a1.n.b;c;d;e1;s.f;g;h;i2.d;n;j;k;l;m;n;o;p;q;r;s;t;u;v;w;p;r3;a.e.u1.k;s3. ;h;t1;r.t4.h;n;r;t;x;z;í;W2.P1.:4.A1.F;I2.B;N1.H.O1.V;R1.F1.C2.N.U.i1.k1.i1.E1.l1.i;X7;a.e.h.i.o.u.y.Y3.e1.t1.h;p;s;[5.A;E;I;a;e;_2._1.i;e;`3.a;e;i;a7; .m1;a1;r1. .n1;d2; .ě.p1;r1;t.r1;t1;í.u1;s1;s1;i1. .v1;u1;t.d3.a1.s1. ;e2.m1. ;r1. ;i2.c1.h1. ;e1.s1.e2.m;r;e8;c1;o1;n1;o1;m1;i1;a.e1;w.l1;i1;t1;e1;i.m1;p1;e1;z.n1;t1;e1;n1;d.s2;a1. .t4;a1; .e1; .i1;m1;a1;r.r1;u1.t.u1.p1. ;w.f3. ;M;y1.i;h9. ;,;.;C;a1.u1.t1;b.e2.i1.r1;a.r1.m1.a1.n;o4.m2.a1; .m;n8; .b.d.e3; .d.y.g.i.k.v.r1.s1. ;u1.r;r1. ;t1;t1;p1;:.i6;b1;n.e1;r.n2;f2;l1;u1;ê.o1;a.s1;t1;a1;l1;a.r1; .s1; .u.k1.u1. ;l3.c1.d;s1. ;v1.a;ma. ;,;R;b1.a.e1.i1.n;f;p;t1.a.u1.l1.t1.i1.c1.a1.m1.p1.i;×;n6. ;V;W;d1; .t;×;o8;c2;h1;o.u1;p.d1;d1;y.f1; .g1;g1;i.no. ;';,;/;a;b;c1.o;d;e2.i;r;f;g;i;l;m;n;o;r;s;t;u;w;y;z;–;r1;i1;g1;e.t1;r1.s;u1;i.r3. ;&;f;s9.,;?;R;f2.e.o.i1.c1.h;l1. ;p2.3;i1. ;r1.g;v3.a.e.i.t2.A;S;uc; ...b2.e;l;f.k2.a;i;m1;a1. .n3;a3; .n5.a;c;n;s;t;r1;y.e2; .i.i8.c2.o1.r1.p;u1.m;d1;i1.o;g1.n;l1.l;m1;o.n;s1.s;v1.o1;c.r5;a.e.i.l.o.s3. ;h;u1.r2;e.p3;a.e.i.t2.m;t;v.w1.a;xb. ;';,;.;8;b;k;l;m1;a.t;y1. ;y1.l;{1.a;|1.a;£1.8;À;Á;Ä;Å;Æ;É;Ò;Ó;Ö;Ü;à;á;æ;è;é1;t3.a;o;u;í;ö;ü1; .Ā;ā;ī;İ;Ō;ō;œ;Ω;α;ε;ω;ϵ;е;–2.e;i;ℓ;";
function fill(node) {
var kidCount = parseInt(dict, 36) || 0,
offset = kidCount && kidCount.toString(36).length;
node.article = dict[offset] == "." ? "a" : "an";
dict = dict.substr(1 + offset);
for (var i = 0; i < kidCount; i++) {
var kid = node[dict[0]] = {}
dict = dict.substr(1);
fill(kid);
}
}
fill(root);
return {
raw: root,
//Usage example: AvsAnSimple.query("example")
//example returns: "an"
query: function (word) {
var node = root, sI = 0, result, c;
do {
c = word[sI++];
} while ('"‘’“”$\''.indexOf(c) >= 0);//also terminates on end-of-string "undefined".
while (1) {
result = node.article || result;
node = node[c];
if (!node) return result;
c = word[sI++] || " ";
}
}
};
})({})
Now, the problem is that I can't find a way to use this function in conjunction with the replaceExpr. The following obviously wouldn't work because of order precedence :
var a = replaceExpr("Theodor is " + AvsAnSimple(zxappearancexz) + "man. He seems rather " + AvsAnSimple(zxpersonalityxz).")
I just recently started learning javascript so my knowledge is rather limited. Any ideas how I could overcome this?
Thank you!
You could use a regular expression to optionally match the " a " or "an" before your word in the input string and store that matched portion in a variable using the String.match() function, then check if that " a " or " an " exists in your matched string, do the manipulations you need to do and store that manipulated string in a separate variable, then use String.replace() to find that previously matched string again, and replace it wit
your manipulated string. The regular expression you could use for this is /(\san?\s)?(zx\w*zx)/gm
See the regular expression here for more context.
Thank you Joseph! With your help I managed to find something that works by using your regular expression. Here's my function :
function replaceExpr(a) {
var nbExprToReplace = 1;
while (nbExprToReplace == 1) {
if (a.search("zx") == -1) {
nbExprToReplace = 0;
} else {
var currentGroup = a.match(/(\san?\s)?(zx\w*xz)/);
var exprToChange = currentGroup[2];
exprToChange = exprToChange.slice(2,-2);
var exprToChange = window[exprToChange];
if (typeof exprToChange !== "function") {
alert("the keyword is not a recognized function!");
break;
} else {
exprToChange = exprToChange();
var final = exprToChange
};
if (currentGroup[1] === undefined) {
} else {
var newArticle = AvsAnSimple.query(exprToChange);
final = newArticle.concat(" " + final)
};
a = a.replace(currentGroup[0], " " + final);
};
};
return a;
};
I'm writing a piece of code to easily save error logs in an object for debugging.
What I'm trying to achieve is to get the Object name from the function it was called from like so:
var MainObject = {
test : function() {
return MainObject.test.caller;
// When called from MainObject.testcaller,
// it should return MainObject.testcaller.
},
testcaller : function() {
return MainObject.test(); // Should return MainObject.testcaller, Returns own function code.
},
anothercaller : function() {
return MainObject.test(); // Should return MainObject.anothercaller, Returns own function code.
}
}
However when I run this code it returns the function code from MainObject.testcaller.
JSFiddle example
Is there any way this is possible?
Update
After looking at Rhumborl's answer, I discovered that assigning the value through another function would lead it to point back at the function name without the object itself.
Code:
(function (name, func) {
MainObject[name] = func;
})('invalid', function() {
return MainObject.test("blah");
});
// This now points at invalid() rather than MainObject.invalid()
Updated fiddle
There is a non–standard caller property of functions that returns the caller function, however that is a pointer to a function object and doesn't tell you the object it was called as a method of, or the object's name. You can get a reference to the function through arguments.callee.
There is also the obsolete arguments.caller, but don't use that. It also provides a reference to the calling function (where supported).
Once you have a reference to the calling function (if there is one), you then have the issue of resolving its name. Given that Functions are Objects, and objects can be referenced by multiple properties and variables, the concept of a function having a particular name is alluvial.
However, if you know that the function is a property of some object, you can iterate over the object's own enumerable properties to find out which one it is.
But that seems to be a rather odd thing to do. What are you actually trying to do? You may be trying to solve a problem that can be worked around in a much more robust and simpler way.
Edit
You can do what you want in a very limited way using the method described above for the case in the OP, however it is not robust or a general solution:
var mainObject = {
test : function() {
var obj = this;
var caller = arguments.callee.caller;
var global = (function(){return this}());
var fnName, objName;
for (var p in global) {
if (global[p] === obj) {
objName = p;
}
}
for (var f in obj) {
if (obj[f] === caller) {
fnName = f;
}
}
return objName + '.' + fnName;
},
testcaller : function() {
return mainObject.test();
},
anothercaller : function() {
return mainObject.test();
}
}
console.log(mainObject.testcaller()); // mainObject.testcaller
console.log(mainObject.anothercaller()); // mainObject.anothercaller
but it's brittle:
var a = mainObject.anothercaller;
console.log(a()); // mainObject.anothercaller
var b = {
foo : mainObject.anothercaller
}
console.log(b.foo()); // mainObject.anothercaller
Oops.
You can use this trick at http://www.eriwen.com/javascript/js-stack-trace/ which throws an error, then parses the stack trace.
I have updated it for the latest versions of Firefox, Chrome and IE. Unfortunately it doesn't work well on my IE9 (and I haven't tested it on Opera).
function getStackTrace() {
var callstack = [];
var isCallstackPopulated = false;
try {
i.dont.exist += 0; //doesn't exist- that's the point
} catch (e) {
if (e.stack) { //Firefox/Chrome/IE11
var lines = e.stack.split('\n');
for (var i = 0, len = lines.length; i < len; i++) {
var line = lines[i].trim();
if (line.match(/^at [A-Za-z0-9\.\-_\$]+\s*\(/)) {
// Chrome/IE: " at Object.MainObject.testcaller (url:line:char)"
var entry = line.substring(3, line.indexOf('(') - 1);
// Chrome appends "Object." to the front of the object functions, so strip it off
if (entry.indexOf("Object.") == 0) {
entry = entry.substr(7, entry.length);
}
callstack.push(entry);
} else if (line.match(/^[A-Za-z0-9\.\-_\$]+\s*#/)) {
// Firefox: "MainObject.testcaller#url:line:char"
callstack.push(line.substring(0, lines[i].indexOf('#')));
}
}
//Remove call to getStackTrace()
callstack.shift();
isCallstackPopulated = true;
} else if (window.opera && e.message) { //Opera
var lines = e.message.split('\n');
for (var i = 0, len = lines.length; i < len; i++) {
if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
var entry = lines[i];
//Append next line also since it has the file info
if (lines[i + 1]) {
entry += lines[i + 1];
i++;
}
callstack.push(entry);
}
}
//Remove call to getStackTrace()
callstack.shift();
isCallstackPopulated = true;
}
}
if (!isCallstackPopulated) { //IE9 and Safari
var currentFunction = arguments.callee.caller;
while (currentFunction) {
var fn = currentFunction.toString();
var fname = fn.substring(fn.indexOf("function") + 8, fn.indexOf('')) || 'anonymous';
callstack.push(fname);
currentFunction = currentFunction.caller;
}
}
return callstack;
}
var MainObject = {
test: function (x) {
// first entry is the current function (test), second entry is the caller
var stackTrace = getStackTrace();
var caller = stackTrace[1];
return caller + "()";
},
testcaller: function () {
return MainObject.test(1, null);
}
}
function SomeFunction() {
return MainObject.test("blah");
}
document.body.innerHTML += '<b style="color: red">' + MainObject.testcaller() + '</b>';
document.body.innerHTML += '<div>Calling SomeFunction() returns: <b style="color: red">' + SomeFunction() + '</b></div>';
MainObject.test() should return: <b style="color: blue">MainObject.testcaller()</b>
<hr />
MainObject.test() returns:
Updated fiddle here
If the text We are sorry but we made a boo boo appears then
Wait 5 seconds
reload
I would like to do this in JavaScript.
Here is an attempt
(function () {
"use strict";
function walkTheDOM(node, func) {
if (node && node.nodeType) {
if (typeof func === "function") {
func(node);
}
node = node.firstChild;
while (node) {
walkTheDOM(node, func);
node = node.nextSibling;
}
}
}
function filterElementsByContains(elements, string) {
var toStringFN = {}.toString,
text = toStringFN.call(elements),
result,
length,
i,
element;
if (text !== "[object NodeList]" && text !== "[object Array]" && !($() instanceof jQuery)) {
return result;
}
result = [];
if (typeof string === "string") {
string = new RegExp("^" + string + "$");
} else if (toStringFN.call(string) !== "[object RegExp]") {
return result;
}
function getText(node) {
if (node.nodeType === 3) {
text += node.nodeValue;
}
}
length = elements.length;
i = 0;
while (i < length) {
text = "";
element = elements[i];
walkTheDOM(element, getText);
if (string.test(text)) {
result.push(element);
}
i += 1;
}
return result;
}
if(filterElementsByContains([document.getElementsByTagName("table")[0]], /We are sorry but we made a boo boo/).length) {
location.reload();
}
The above could should, I think, work for the text if it appears in a specific place. I want to make it more general - so that the text could appear anywhere on that page.
Also, I would like to know how to add a pause so that, for example, it waits 5 seconds before reloading.
I guess I would add incorporate something like:
setTimeout(
function()
{
//location.reload();
}, 5000);
Just do an indexOf on the body's textContent/innerText property
var content = document.body.textContent || document.body.innerText;
var hasText = content.indexOf("We are sorry but we made a boo boo")!==-1;
if(hasText){
setTimeout(function(){
window.location = "http://www.example.com";
},5000);
}
This may work:
var bodyText = document.body.textContent || document.body.innerText;
var msg = "We are sorry but we made a boo boo";
if (bodyText.indexOf(msg) > -1) {
setTimeout(function() {
location.reload();
}, 5000);
}
--sorry for nearly duplicate answer :\ --
--edit--
Tell me - how can I add a second rule, it's a different way of
phrasing the error message: There was an internal error in our system.
We logged the problem and will investigate it later.
This will check for both messages:
var bodyText = document.body.textContent || document.body.innerText;
var msg = [
"We are sorry but we made a boo boo",
"There was an internal error in our system. We logged the problem and will investigate it later."
];
var flag = false;
for (var i = 0; i < msg.length; i++) {
if bodyText.indexOf(msg[i]) {
flag = true;
}
}
if (flag) {
setTimeout(function() {
location.reload();
}, 5000);
}
Explanation: All I did was modify msg to be an array of strings rather than a string itself. Then for every msg we want to check, we loop through the values and compare msg against bodyText. If bodyText contains one of the msg's, we set a flag to true, and then perform an if statement on flag.
If you want to check anywhere in the page... then you have to do just that. Get every DOM element and check if there is your String there... I do not think there is another way.
Yes using setTimeout will do the trick for waiting before reload.
(function (window, undefined){
var _eles = [],
_target, source, mobile, destory;
if (!document.getElementsByClassName) {
document.getElementsByClassName = function (classname) {
var elArray = [];
var tmp = document.getElementsByTagName("*");
var regex = new RegExp("(^|\\s)" + classname + "(\\s|$)");
for (var i = 0; i < tmp.length; i++) {
if (regex.test(tmp[i].className)) {
elArray.push(tmp[i]);
}
}
return elArray;
};
}
//if ((/msie 7/gi).test(navigator.appVersion)) {
// console.log('true')
//}
var uTube = {
init: function (opts) {
var nodes = ["www.youtube.com/watch?v=", "youtu.be/", "www.youtube.com/embed/", "www.youtube.com/v/", "youtube.com/watch?feature"],
vers = opts.version,
i;
switch (vers) {
case "phpbb3":
vers = 'content';
break;
case "phpbb2":
vers = 'postbody';
break;
case "punbb":
vers = 'entry-content';
break;
case "invision":
vers = 'postbody';
break;
}
_target = document.getElementsByClassName('post');
for (i = 0; i < _target.length; i++) {
_eles.push(_target[i].getElementsByClassName(vers));
}
console.log(_eles);
return {
source: function (opt) {
console.log(_eles);
},
mobile: function (opt) {
console.log('we are now' + opt.text);
return {
destroy: function () {
console.log('destroyed');
}
};
}
};
}
};
return (window.utube = window._$ = uTube.init);
})(window);
I am trying to find a way to test my code on browsers that may not support some of my methods. for when I try in IE7 and 8 I get an error saying Unable to get property 'mobile' of undefined or null reference
Code Initiation looks like this:
_$({
version:"phpbb3"
}).mobile({text:"mobile version"}).destroy();
Right now the properties are just logging certain things for testing purposes. Though like I said it's not working in IE7 or 8, haven't tested 9 yet until 7 and 8 are done. Is there something in particular that I should change for IE7+ in my code that you can see off hand if not is there a site that can give me a close range of what is wrong?
I think you mean to put break instead of return in the switch blocks.
I am using Typeahead by twitter. I am running into this warning from Intellij. This is causing the "window.location.href" for each link to be the last item in my list of items.
How can I fix my code?
Below is my code:
AutoSuggest.prototype.config = function () {
var me = this;
var comp, options;
var gotoUrl = "/{0}/{1}";
var imgurl = '<img src="/icon/{0}.gif"/>';
var target;
for (var i = 0; i < me.targets.length; i++) {
target = me.targets[i];
if ($("#" + target.inputId).length != 0) {
options = {
source: function (query, process) { // where to get the data
process(me.results);
},
// set max results to display
items: 10,
matcher: function (item) { // how to make sure the result select is correct/matching
// we check the query against the ticker then the company name
comp = me.map[item];
var symbol = comp.s.toLowerCase();
return (this.query.trim().toLowerCase() == symbol.substring(0, 1) ||
comp.c.toLowerCase().indexOf(this.query.trim().toLowerCase()) != -1);
},
highlighter: function (item) { // how to show the data
comp = me.map[item];
if (typeof comp === 'undefined') {
return "<span>No Match Found.</span>";
}
if (comp.t == 0) {
imgurl = comp.v;
} else if (comp.t == -1) {
imgurl = me.format(imgurl, "empty");
} else {
imgurl = me.format(imgurl, comp.t);
}
return "\n<span id='compVenue'>" + imgurl + "</span>" +
"\n<span id='compSymbol'><b>" + comp.s + "</b></span>" +
"\n<span id='compName'>" + comp.c + "</span>";
},
sorter: function (items) { // sort our results
if (items.length == 0) {
items.push(Object());
}
return items;
},
// the problem starts here when i start using target inside the functions
updater: function (item) { // what to do when item is selected
comp = me.map[item];
if (typeof comp === 'undefined') {
return this.query;
}
window.location.href = me.format(gotoUrl, comp.s, target.destination);
return item;
}
};
$("#" + target.inputId).typeahead(options);
// lastly, set up the functions for the buttons
$("#" + target.buttonId).click(function () {
window.location.href = me.format(gotoUrl, $("#" + target.inputId).val(), target.destination);
});
}
}
};
With #cdhowie's help, some more code:
i will update the updater and also the href for the click()
updater: (function (inner_target) { // what to do when item is selected
return function (item) {
comp = me.map[item];
if (typeof comp === 'undefined') {
return this.query;
}
window.location.href = me.format(gotoUrl, comp.s, inner_target.destination);
return item;
}}(target))};
I liked the paragraph Closures Inside Loops from Javascript Garden
It explains three ways of doing it.
The wrong way of using a closure inside a loop
for(var i = 0; i < 10; i++) {
setTimeout(function() {
console.log(i);
}, 1000);
}
Solution 1 with anonymous wrapper
for(var i = 0; i < 10; i++) {
(function(e) {
setTimeout(function() {
console.log(e);
}, 1000);
})(i);
}
Solution 2 - returning a function from a closure
for(var i = 0; i < 10; i++) {
setTimeout((function(e) {
return function() {
console.log(e);
}
})(i), 1000)
}
Solution 3, my favorite, where I think I finally understood bind - yaay! bind FTW!
for(var i = 0; i < 10; i++) {
setTimeout(console.log.bind(console, i), 1000);
}
I highly recommend Javascript garden - it showed me this and many more Javascript quirks (and made me like JS even more).
p.s. if your brain didn't melt you haven't had enough Javascript that day.
You need to nest two functions here, creating a new closure that captures the value of the variable (instead of the variable itself) at the moment the closure is created. You can do this using arguments to an immediately-invoked outer function. Replace this expression:
function (item) { // what to do when item is selected
comp = me.map[item];
if (typeof comp === 'undefined') {
return this.query;
}
window.location.href = me.format(gotoUrl, comp.s, target.destination);
return item;
}
With this:
(function (inner_target) {
return function (item) { // what to do when item is selected
comp = me.map[item];
if (typeof comp === 'undefined') {
return this.query;
}
window.location.href = me.format(gotoUrl, comp.s, inner_target.destination);
return item;
}
}(target))
Note that we pass target into the outer function, which becomes the argument inner_target, effectively capturing the value of target at the moment the outer function is called. The outer function returns an inner function, which uses inner_target instead of target, and inner_target will not change.
(Note that you can rename inner_target to target and you will be okay -- the closest target will be used, which would be the function parameter. However, having two variables with the same name in such a tight scope could be very confusing and so I have named them differently in my example so that you can see what's going on.)
In ecmascript 6 we have new opportunities.
The let statement declares a block scope local variable, optionally initializing it to a value.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/let
Since the only scoping that JavaScript has is function scope, you can simply move the closure to an external function, outside of the scope you're in.
Just to clarify on #BogdanRuzhitskiy answer (as I couldn't figure out how to add the code in a comment), the idea with using let is to create a local variable inside the for block:
for(var i = 0; i < 10; i++) {
let captureI = i;
setTimeout(function() {
console.log(captureI);
}, 1000);
}
This will work in pretty much any modern browser except IE11.