It will make selection words starting with "p" and ending with "a". Why it didnt work?
function checkWord(word) {
if (word.charAt(0) = 'p' && word.charAt(word.length - 1) = 'a') {
return true;
} else {
return false;
}
= is used for assigning values, not checking them. Use == for checking the values and === for checking value and types. So, your code should be like:
function checkWord(word) {
if (word.charAt(0) === 'p' && word.charAt(word.length - 1) === 'a') {
return true;
} else {
return false;
}
This should do the trick.
You didn't put 2 equals to if you only put 1 equals you are assigning it and if you put 2 equals you're comparing it the. below code should help
/* Check weather the first letter is equals to p and the last letter is equals to a. */
function checkWord(word) {
let firstPAndLastA = false;
if(word != null){
if (word.charAt(0) == 'p' && word.charAt(word.length - 1) == 'a') {
firstPAndLastA = true;
} else {
firstPAndLastA = false;
}
}
return firstPAndLastA;
}
//Calling Function
console.log(checkWord("ppoa"))
Related
I have a code below
function createRoom(){
$(document).keyup(function(event) {
if ($("#room_name").is(":focus") && event.key == "Enter") {
var plainText = document.querySelector(".create-room-class").value;
var createRoomName = plainText.replace(/(<([^>]+)>)/gi, "");
createRoomName = createRoomName.replace(/ +/g, "");
createRoomName = createRoomName.trim();
if(createRoomName.length == 0){
alert("empty");
} else if(createRoomName.length < 5){
alert("Room name must be equal or longer than 5 characters");
} else if(!createRoomName.length == 0)
{
getCreatedRoomName(createRoomName);
window.location = createRoomName;
}
}
});
}
createRoom();
function getCreatedRoomName(x){
return x;
}
What it does is first checks if input field is not empty and if not smaller than 5 characters. If everything is fine then we pass that value to a function and then redirect to that created name url. Look below.
getCreatedRoomName(createRoomName);
window.location = createRoomName;
And we return value (return x)
function getCreatedRoomName(x){
return x;
}
How can I retrieve that returned value in nodejs? I tried modules it doesn't work for some reason.
I have solved the problem Count the smiley faces:
Given an array (arr) as an argument complete the function countSmileys that should return the total number of smiling faces.
Rules for a smiling face:
Each smiley face must contain a valid pair of eyes. Eyes can be marked as : or ;
A smiley face can have a nose but it does not have to. Valid characters for a nose are - or ~
Every smiling face must have a smiling mouth that should be marked with either ) or D
No additional characters are allowed except for those mentioned.
Valid smiley face examples: :) :D ;-D :~)
Invalid smiley faces: ;( :> :} :]
Example
countSmileys([':)', ';(', ';}', ':-D']); // should return 2;
countSmileys([';D', ':-(', ':-)', ';~)']); // should return 3;
countSmileys([';]', ':[', ';*', ':$', ';-D']); // should return 1;
Note
In case of an empty array return 0. You will not be tested with invalid input (input will always be an array). Order of the face (eyes, nose, mouth) elements will always be the same.
Then when I look through the solutions I find that many people use regexp. Then I want write a state machine to implement regexp and solve this problem. But I failed. This is my code:
function countSmileys(smileys) {
let state = smileyHasValidEye;
return smileys.filter(smiley => {
for (let s of [...smiley]) {
state = state(s);
}
return state === true;
}).length;
}
function smileyHasValidEye(s) {
if (s === ':' || s === ';') {
return smileyHasValidNose;
}
return smileyHasValidEye;
}
function smileyHasValidNose(s) {
if (s === '-' || s === '~') {
return smileyHasValidMouth;
}
return smileyHasValidMouth(s);
}
function smileyHasValidMouth(s) {
if (s === ')' || s === 'D') {
return true;
}
return;
}
console.log(countSmileys([':)', ';(', ';}', ':-D']));
And the error I get is:
state = state(s);
^
TypeError: state is not a function
Then I debugged my code I found the procedure doesn't enter the smileyHasValidNose function. Then I don't know the reason.
The problem is you don't really reset state in between smileys. So the next smiley state will be true which you can't call (it's not a function).
You could use a local variable for state that resets it to the first function (the first step).
function countSmileys(smileys) {
let firstStep = smileyHasValidEye;
return smileys.filter(smiley => {
let state = firstStep;
for (let s of [...smiley]) {
state = state(s);
}
return state === true;
}).length;
}
function smileyHasValidEye(s) {
if (s === ':' || s === ';') {
return smileyHasValidNose;
}
return smileyHasValidEye;
}
function smileyHasValidNose(s) {
if (s === '-' || s === '~') {
return smileyHasValidMouth;
}
return smileyHasValidMouth(s);
}
function smileyHasValidMouth(s) {
if (s === ')' || s === 'D') {
return true;
}
return;
}
console.log(countSmileys([':)', ';(', ';}', ':-D']));
This code however, will error if there's more on the string besides the smiley (or a partial of the smiley).
I would change smileyHasValidMouth to return false if it doesn't detect a smiley. Just to be more consistent here...
function smileyHasValidMouth(s) {
if (s === ')' || s === 'D') {
return true;
}
return false;
}
And adjust your loop to exit early if it finds a value that is not a function.
for (let s of [...smiley]) {
state = state(s);
if(typeof state !== 'function') return state;
}
function countSmileys(smileys) {
let firstStep = smileyHasValidEye;
return smileys.filter(smiley => {
let state = firstStep;
for (let s of [...smiley]) {
state = state(s);
if (typeof state !== 'function') return state;
}
}).length;
}
function smileyHasValidEye(s) {
if (s === ':' || s === ';') {
return smileyHasValidNose;
}
return smileyHasValidEye;
}
function smileyHasValidNose(s) {
if (s === '-' || s === '~') {
return smileyHasValidMouth;
}
return smileyHasValidMouth(s);
}
function smileyHasValidMouth(s) {
if (s === ')' || s === 'D') {
return true;
}
return false;
}
console.log(countSmileys([':~(', ':>', ':D', ':(', ':o>', ';)', ':)']));
I'm trying to use the Event delegation/switch statement for the first time in my life, and I'm having trouble with for loop. When it was 'array[i]' it wasn't a problem. But now I'm removing the for loop to use the event delegation and putting it inside of a function, it keeps giving me errors, and I don't know what parameter can replace (and make the code work again) that array[i] in the new function. Any help or explanation will be appreciated.
//original code
const numbers = document.querySelectorAll(".number");
for (let i = 0; i < numbers.length; i++) {
numbers[i].addEventListener("click", function () {
if (display.value.length < 13) {
return;
}
if (display.value == "0" && numbers[i] != dot) {
display.value = numbers[i].innerText;
calculation = display.value;
} else {
if (numbers[i] == dot && display.value.includes(".")) {
return;
} else if (numbers[i] == dot && display.value == "") {
return;
} else {
display.value += numbers[i].innerText;
calculation = display.value;
}
}
buttonEffect(numbers[i], "number-active");
});
}
// New code
const numbers = document.querySelectorAll(".number");
function numberClick(number) {
if (display.value.length > 13) {
return;
}
if (display.value == "0" && this != dot) {
display.value = number.innerText;
calculation = display.value;
} else {
if (numbers == dot && display.value.includes(".")) {
return;
} else if (number == dot && display.value == "") {
return;
} else {
display.value += number.innerText;
calculation = display.value;
}
}
operatorOnOff = false;
buttonEffect(number, "number-active");
}
document.querySelector(".wrapper").addEventListener("click", (e) => {
switch (e.target.dataset.key) {
case "number":
numberClick();
break;
}
});
You pass the element that was the target of the click into numberClick and use it where previously you used numbers[i]. It looks like you're already doing the second part of that, and you even have a parameter declared for it, you just need to pass the element in:
numberClick(e.target);
Note that if your .number elements have child elements, target may be one of those child elements rather than .number. To handle that, you can use the DOM's relatively-new closest method, probably combined with contains to make sure it didn't match something surrounding .wrapper:
document.querySelector(".wrapper").addEventListener("click", (e) => {
const number = e.target.closest(".number");
if (number && this.contains(number) && number.dataset.key) {
numberClick(number);
}
});
There are polyfills you can use if you need to support obsolete browsers, or just do the loop yourself:
document.querySelector(".wrapper").addEventListener("click", (e) => {
let number = e.target;
while (number && !number.matches(".number")) {
if (this === number) {
return; // Reached the wrapper without finding it
}
number = number.parentElement;
}
if (number && number.dataset.key) {
numberClick(number);
}
});
I am trying to make a filter based on checkboxes.
The thing is js ignoring other conditions inside filter when one is active
filterData() {
return this.airlines.filter(x => {
if (this.filters.options.length != 0 || this.filters.airlines.length != 0) {
for (let i = 0; this.filters.options.length > i; i++) {
if (this.filters.options[i] == 0) {
return x.itineraries[0][0].stops == 0;
}
if (this.filters.options[i] == 1) {
return x.itineraries[0][0].segments[0].baggage_options[0].value > 0;
}
}
} else {
return x;
}
})
}
I know that return will stop the current loop, but is there any way to do it correctly?
Update-1: (When to filter record for every case checked OR case)
Replace for loop and all conditions in a single return by && for if and || condition for data:
var chbox = this.filters.options;
return $.inArray(0, chbox) != -1 && x.itineraries[0][0].stops == 0
|| $.inArray(1, chbox) != -1 && x.itineraries[0][0].segments[0].baggage_options[0].value > 0;
Hope this helps !!
$.inArray(value, arr) method will check for each checkboxes and will work for every checked ones .
Update-2 (When to filter record for every case checked AND case)
As per comment below, you are trying to use checkbox on demand so use below code:
var chbox = this.filters.options;
boolean condition = true;
if ($.inArray(0, chbox) != -1) {
conditon = conditon && x.itineraries[0][0].stops == 0;
}
if ($.inArray(1, chbox) != -1) {
conditon = conditon && x.itineraries[0][0].segments[0].baggage_options[0].value > 0;
}
return condition;
Your filter function is returning an object, which ideally should be a boolean value. Please refactor the code as below.
filterData() {
return this.airlines.filter(x => {
let result = false;
if (this.filters.options.length != 0 || this.filters.airlines.length != 0) {
for (let i = 0; this.filters.options.length > i; i++) {
if (this.filters.options[i] == 0) {
result = x.itineraries[0][0].stops == 0;
break;
} else if (this.filters.options[i] == 1) {
result = x.itineraries[0][0].segments[0].baggage_options[0].value > 0;
break;
}
}
}
return result;
})
}
Is there's a way to change the filter from sensitive case to insensitive?
Thank you.
Here’s the relevant section of a working example using the DataView filter. Notice the searchString variable is converted to lowercase when the value is first defined and then it's compared to lowercase strings within the myFilter function.
function myFilter(item, args) {
if (args.searchString != "" && item["FirstName"].toLowerCase().indexOf(args.searchString) == -1 && item["LastName"].toLowerCase().indexOf(args.searchString) == -1) {
return false;
}
return true;
}
....
$("#txtSearch").keyup(function (e) {
Slick.GlobalEditorLock.cancelCurrentEdit();
// clear on Esc
if (e.which == 27) {
this.value = "";
}
searchString = this.value.toLowerCase();
updateFilter();
});
function updateFilter() {
dataView.setFilterArgs({
searchString: searchString
});
dataView.refresh();
}
// initialize the model after all the events have been hooked up
dataView.beginUpdate();
dataView.setItems(data);
dataView.setFilterArgs({
searchString: searchString
});
dataView.setFilter(myFilter);
dataView.endUpdate();
Guessing you are talking about the DataView filter, the implementation of the filter functionality is totally up to you. Note the filter function used in the SlickGrid examples - that function is set as the filter using dataView.setFilter(your_function_here). So implement the filter function as you want and set it to the dataView
function filter(item) {
// String Should Match Each Other
/* for (var columnId in columnFilters) {
if (columnId !== undefined && columnFilters[columnId] !== "") {
var c = grid.getColumns()[grid.getColumnIndex(columnId)];
if (item[c.field] != columnFilters[columnId]) {
return false;
}
}
} */
for (var columnId in columnFilters) {
if (columnId !== undefined && columnFilters[columnId] !== "") {
var c = grid.getColumns()[grid.getColumnIndex(columnId)];
// This Case Sensitive
//if (!(item[c.field] && (""+item[c.field]).indexOf(columnFilters[columnId]) !== -1)) {
if (!(item[c.field] && (""+item[c.field].toLowerCase()).indexOf(columnFilters[columnId].toLowerCase()) !== -1)) {
// Case in-Sensitive
return false;
}
}
}
return true;
}