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Angular 2 - if condition getting true for all values

I have been stuck at a point, my if condition is returning true for all conditions, I am checking that a value is greater or not.
Code:
hideAmountModal() {
var self = this;
self.home_delivery_charge = self.storeService.fetchHomedeliveryData(self.shopId);
self.home_delivery_charge.subscribe((res: any) => {
for (var i = 0; i < res.length; i++) {
if (self.deliveryData.delivery_charge > res[i].amount) {
self.check_delivery_charge = true;
console.log('Deliverycharge',self.deliveryData.delivery_charge,'result',res[i].amount);
console.log('deliver charge is greater',self.check_delivery_charge);
}
else if (self.deliveryData.delivery_charge < res[i].amount){
self.check_delivery_charge = false;
}
}
})
self.DeliveryChargeValue = true
self.selectAmountModal.hide();
}
From the console what I get is below:
Where have I gone wrong?

Try converting both values to number type
if (parseInt(self.deliveryData.delivery_charge) > parseInt(res[i].amount)) {
}

Change your if condition from:
if (self.deliveryData.delivery_charge > res[i].amount)
To this:
if (Number(self.deliveryData.delivery_charge) > Number(res[i].amount))
Doing this, you would be explicitly type-casting your input type into number.
Remember: You'll get NaN (Not-a-Number) if your input can't be converted to number type.
In case you don't want this behavior you could always use parseInt which uses Javascript's Number() function under-the-hood as shown here.

Be careful because you are not handling the equal case, which you should include on the else if. Can you check that the values that you are comparing are numbers? This is probably the problem.

You console.log only value when is true
Try add console.log here :
else if(self.deliveryData.delivery_charge < res[i].amount) {
self.check_delivery_charge = false;
}

Javascript Basic algorithm

Return true if the string in the first element of the array contains all of the letters of the string in the second element of the array. No case-sensitivity and order doesn't matter only the letters matter. For ex - ["Hello","hello"] returns true and so does ["Alien","lien"] and also ["Mary", "Aarmy"]. I think you get it. If not return false.
I could solve it with Array.indexOf() === -1 (in the first for loop) but can it work with this code, it's the opposite. I just can't make it return false. Ultimately, I wanna know, can you make it return false without changing the method.
function mutation(arr) {
var split = arr[1].toLowerCase().split("");
var splitSecond = arr[0].toLowerCase().split("");
for(k=0;k<=arr[0].length;k++){
for(i=0;i<=arr[1].length;i++){
if(split[i]===splitSecond[k]) {
return true
}
}
} return false
}
mutation(["hello", "hney"], "");
If using any other method, explain :)

The problem with your code is that you return true; as soon as one letter matches.
What you need to do is check if all letters match, which is easier achieved by checking if any letter doesn't match.
mainloop:
for(k=0;k<=arr[0].length;k++){
for(i=0;i<=arr[1].length;i++){
if(split[i]===splitSecond[k]) {
continue mainloop; // found the letter, move on to next search
}
}
return false; // failed to find letter, fail here
}
return true; // haven't failed yet and end of input reached. Success!
Another alternative would be:
for(k=0;k<arr[0].length;k++) {
if( arr[1].indexOf(split[k]) < 0) {
// letter not found
return false;
}
}
// not failed yet? Excellent!
return true;

function mutation(arr) {
var test = arr[0].toLowerCase(),
chars = arr[1].toLowerCase(),
len=chars.length;
for(var i=0;i<len;i++)
if(test.indexOf(chars[i])==-1) //this char not exist in test string
return false;
return true;//all chars already checked
}
mutation(["hello", "he"]);
https://jsfiddle.net/hb2rsm2x/115/

Here is an interesting way using regular expressions. escapeRegExp was taken from here.
function mutation(arr){
var matcher = new RegExp('[^'+escapeRegExp(arr[1])+']', "i");
return arr[0].match(matcher) === null;
}
function escapeRegExp(s) {
return s.replace(/[-/\\^$*+?.()|[\]{}]/g, '\\$&')
}

JavaScript Throws Undefined Error

What it is supposed to do -
Example
url1(pages,"ALT") returns "www.xyz.ac.uk"
url1(pages,"xyz") returns ""
The error - TypeError: Cannot call method 'toUpperCase' of undefined
This is just for some coursework, Im stuck with these errors. Any help would be much appreciated
function index(string,pattern,caseSensitive) {
if(caseSensitive == false) {
var v = string.toUpperCase();
} else {
var v = string;
}
return indexNumber = v.indexOf(pattern);
}
var pages = [ "|www.lboro.ac.uk|Loughborough University offers degree programmes and world class research.", "!www.xyz.ac.uk!An alternative University" , "%www%Yet another University"];
alert(url1(pages, "ALT"));
function url1(pages,pattern) {
var siteContent = [];
for(i=0;i<pages.length;i++) {
var seperator = pages[i].charAt(0);
if(pages[i].indexOf(seperator)>0){
siteContent = pages[i].split(pages[i].indexOf(seperator));
}
if( index(siteContent[2],pattern,false)>=0){
return siteContent[1];
}else{
return "";
}
}
}

if(pages[i].indexOf(seperator)>0){
siteContent = pages[i].split(pages[i].indexOf(seperator));
}
if( index(siteContent[2],pattern,false)>=0){
return siteContent[1];
}else{
return "";
}
If pages[i].indexOf(seperator)<=0, siteContent is still whatever it was from the last iteration. If that happens on the first iteration, siteContent is still [], and siteContent[2] is undefined.
Another problem: the expression pages[i].indexOf(seperator) returns a number, and pages[i].split expects a delimiting string as an argument. Since the number doesn't appear in your input, you'll always get a single-element array, and siteContent[2] will always be undefined. Get rid of .indexOf(seperator), change it to siteContent = pages[i].split(seperator).
One more: get rid of the else { return ""; }. Add a return ""; after the for loop.
Finally, in the first if statement condition, change .indexOf(seperator) > 0 to .indexOf(seperator, 1) !== -1. Since you're getting seperator from the first character of the string, it will be found at 0. You want the second occurrence, so start the search at 1. In addition, .indexOf returns -1 if it doesn't find the substring. You'll need to account for this in both if conditions.
Side note, as this is not causing your problem: never use == false. JS will coerce stuff like 0 and "" to == false. If that's what you want, just use the ! operator, because the expression has nothing to do with the value false.
My final answer is http://jsfiddle.net/QF237/

Right here:
alert(url1(pages, ALT)); // ALT ISN'T DEFINED
I believe you forgot to quote it:
alert(url1(pages, "ALT"));

You should split the string passing the separator character itself. Your function then will look like:
function url1(pages,pattern) {
var siteContent = [];
for(i=0;i<pages.length;i++) {
var seperator = pages[i].charAt(0);
console.log(seperator);
if(pages[i].indexOf(seperator)>=0){
siteContent = pages[i].split(seperator); //fixed here
}
console.log(siteContent);
if( index(siteContent[2],pattern,false)>=0){
return siteContent[1];
}else{
return "";
}
}
}
Tell us if it worked, please.
EDIT: It seeems your index() also has a little problem. Please try the function below.
function index(string,pattern,caseSensitive) {
var v;
if(caseSensitive == false) {
v = string.toUpperCase();
pattern = pattern.toUpperCase(); //to clarify: pattern should be uppercased also if caseSensitiveness is false
} else {
v = string;
}
return v.indexOf(pattern);
}
EDIT 2:
And url1() is finally like this:
function url1(pages,pattern) {
var siteContent = [];
for(i=0;i<pages.length;i++) {
var seperator = pages[i].charAt(0);
if(pages[i].indexOf(seperator)>=0){
siteContent = pages[i].split(seperator);
}
if( index(siteContent[2],pattern,false)>=0){
return siteContent[1];
}
}
return "";
}
In this case, the first occurrence of pattern in all pages will be returned.

If Else Conditionals within Function in JavaScript

I'm having issues with conditionals. I want to return the index where pattern starts in string (or -1 if not found). The search is to be case sensitive if the 3rd parameter is true otherwise it is case insensitive.
Examples
index("abAB12","AB",true) returns 2 but index("abAB12","AB",false) returns 0
index("abAB12","BA",true) returns -1 and index("abAB12","BA",false) returns 1
Any idea how I can accomplish this?
This is my code so far
var s = "abAB12"
var p = "AB"
var cs = true
function index(string, pattern, caseSensitive) {
if (pattern) {
var found = false;
if (caseSensitive = false) {
if (string.indexOf(pattern.) >= 0) {
found = true;
}
return (found);
else {
return ("");
}
} else if (caseSensitive = true) {
if (string.toLowerCase().indexOf(pattern.toLowerCase()) >= 0) {
found = true;
}
return (found);
} else {
return ("");
}
}
}
alert(index(s, p, cs));
Fiddle at http://jsfiddle.net/AfDFb/1/

You have some mistype in your code. On the 15th line you have
}
return (found);
else {
This is not not valid. Change it to
return (found);
}
else {
There is another one.
if (caseSensitive = false) {
= used for assignment. You need to use == in if statements when comparing.
Also on the 13th line, there's an extra . after pattern. Remove it.
if (string.indexOf(pattern.) >= 0) {
Your fiddle example

You can use string.search() with a regular expression to accomplish this in one liner:
function index(input, key, caseMatters) {
return input.search(new RegExp(key, caseMatters ? '' : 'i'));
}
Now you can:
index("abAB12","AB",true); // returns 2
index("abAB12","AB",false); // returns 0
index("abAB12","BA",true); // returns -1
index("abAB12","BA",false); // returns 1

You need to use double equals sign == in your if, else statements.
if(caseSensitive == false)
And
if(caseSensitive == true)

You are assigning value inside if condition instead of comparing it.
Try
if (caseSensitive == false) {
and
if(caseSensitive == true)

You'd better use search :
'abAB12'.search(/AB/); // 2
'abAB12'.search(/AB/i); // 0
'abAB12'.search(/BA/); // -1
'abAB12'.search(/BA/i); // 1
The i flag means "case insensitive" ( insensible à la casse :D ).

Javascript behaving weirdly

the following function does not work as I thought it should have. For some reason, the loop breaks whenever one the the validate function returns false. Why is that?
Here is my code :
function validateGroup(input) {
if (!input.value.match(/^[0-9]{0,2}$/)) {
$(input).addClass("invalidField");
return false;
}
$(input).removeClass("invalidField");
return true;
}
function validateClass(input) {
if (!input.value.match(/^[a-zA-Z0-9-]{0,9}$/)) {
$(input).addClass("invalidField");
return false;
}
$(input).removeClass("invalidField");
return true;
}
function validateData() {
var rows = document.getElementsByTagName("tbody")[0].getElementsByTagName("tr");
var valid = true;
for (var i = 0, arrayLength = rows.length; i < arrayLength; ++i) {
valid = valid && validateClass(rows[i].getElementsByTagName("input")[0]);
valid = valid && validateGroup(rows[i].getElementsByTagName("input")[1]);
valid = valid && validateGroup(rows[i].getElementsByTagName("input")[2]);
}
return valid;
}
Thanks a lot!

the statement valid && validateClass(...) will not call the validateClass method if valid is false. I think what you want to do is change the order of those to
valid = validateClass(rows[i].getElementsByTagName("input")[0]) && valid;
valid = validateGroup(rows[i].getElementsByTagName("input")[1]) && valid;
valid = validateGroup(rows[i].getElementsByTagName("input")[2]) && valid;
Javascript doesn't bother evaluating the rest of an && expression if it already knows that the result is false.

It looks like you want to run the validate functions on each iteration even if ‘valid’ was already set to false. However the && operation you are using will short-circuit, so although the loop will continue the validate functions will not be called on subsequent iterations.
A really simple alternative which would work the way you want would be:
for (var i = 0, arrayLength = rows.length; i < arrayLength; ++i) {
if(!validateClass(rows[i].getElementsByTagName("input")[0])) valid = false;
if(!validateGroup(rows[i].getElementsByTagName("input")[1])) valid = false;
if(!vvalidateGroup(rows[i].getElementsByTagName("input")[2])) valid = false;
}

It sounds like that is the intent of the function. The three lines of
valid = valid && validate...
mean that if any of the validate functions ever hits false valid will remain false for the rest of the loop.

I think it's because of the lazy evaluation scheme Javascript uses with &&. Try a single & instead.
Short-circuit evaluation: Support in common programming languages

It's called short-circuiting. Quick fix: replace each line with
valid = validateClass(rows[i].getElementsByTagName("input")[0]) && valid;