"Encountered an error when using the pop method on a split function: 'undefined is not

I am working with an array of filenames called ret, and I need to extract the extension of each file name.

var cList="";
var fName="";
var ext="";
for(var i=0;i<=ret.length-1;i++){                       
    fName=ret[i];               
    ext=fName.split('.').pop();
    if(ext=="msi"){
        cList+="<br><span class='bld'>Yield Monitor Simulators</span><p>";
    }   
    cList+="<a target='_blank' href='"+httpBase+"cheatsheets/"+fName+"'>"+fName+"</a><br>";
}

However, when I try to split the filename using:

ext=fName.split('.').pop();

I encounter the error message:

"Uncaught TypeError: undefined is not a function"

If I comment out that line, the list of files is displayed as expected.

var cList="";
var fName="";
var ext="";
for(var i=0;i<=ret.length-1;i++){                       
    fName=ret[i];               
    //ext=fName.split('.').pop();
    if(ext=="msi"){
        cList+="<br><span class='bld'>Yield Monitor Simulators</span><p>";
    }   
    cList+="<a target='_blank' href='"+httpBase+"cheatsheets/"+fName+"'>"+fName+"</a><br>";
}

The JSFiddle example works fine, so the issue seems to be within my code...

javascriptarrayssplit

Answer №1

To fix the issue, the fName variable needed to have toString() added to it.

fName=ret[i].toString();

It appears that a value retrieved from an array of string values is not automatically recognized as a string.

Further changes made included:

for(var i=0;i<=ret.length-1;i++){                   
      console.log(i, ret[i]);
      console.log(i, ret[i], ret[i].split('.'), ret[i].split('.').pop());       
        fName=ret[i].toString();

The first iteration resulted in the following message in the console:

0 ["2020.pdf"] index.js:115
Uncaught TypeError: undefined is not a function

Answer №2

The variable "ret" actually contains an array of arrays, each containing a string. It's not just a simple array of strings as you might expect. Take a closer look at the values stored in "ret":

[] represents an empty array in JavaScript
["astring"] is an array that contains a string
["astring", 99] is an array with a string at index 0 and a number at index 1

If you log the value of "ret" before your loop, you will likely see something like this:

[["string"], ["string"], ["string"]...]
instead of ["string", "string", "string"...]

It seems like there are some syntax errors in your JavaScript code. Time to revisit and revise your JavaScript syntax for better results.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

An assortment of the most similar values from a pair of arrays

I am seeking an algorithm optimization for solving a specific problem that may be challenging to explain. My focus is not on speed or performance, but rather on simplicity and readability of the code. I wonder if someone has a more elegant solution than mi ...

javascriptarraysalgorithmoptimization

Displaying grid in object in threejs: a tutorial

I currently have a horizontal grid Helper and polygon within my scene. Is there a way to hide the grid outside of the polygon, similar to the image below? https://i.sstatic.net/pQ40h.png Here is the JSFiddle var camera, scene, renderer, controls, geo ...

javascriptthree.js

Guide to changing the content zoom factor of UWP WebView

Looking to reset the content zoom factor of a webview in C# UWP to 1 or 100%. How can this be achieved? Is there a way to instruct the webview itself to scale back to 1.0 using C#? Something like webView.ContentScale = 1.0; Alternatively, what code ne ...

javascriptc#htmluwp

What is the process for making the default text in a text box appear grayed out?

Hey there! I have this cool idea for a text box. Basically, it starts off with default text but when you hover your mouse over it, the text disappears and you can start typing as usual: If you want to see how it looks like, you can check out this link: N ...

javascriptcss

Is there a way to dynamically update the path in react using react-router-dom?

Is there a way to fix the issue with updating the path dynamically using an API call in the router? The problem I'm facing is that when I click on the navigation menu, it loads perfectly the first time. However, if I refresh the page, I get a 404 erro ...

javascriptreactjsreact-router-dom

"Customize the appearance of a List Element in Material UI by changing

How can I modify the color of a specific material ui list item? <ListItemText primary={mspvar} secondary="buy"> ...

javascriptreactjsmaterial-ui

Execute the gulp module on the source files

Recently, I've been delving into the world of gulp and trying to enhance the readability of my js source files. I have a task in place (which executes successfully) that utilizes 'gulp-beautify' to beautify the js files: gulp.task('js& ...

javascriptnode.jsnpmgulp

retrieve room from a socket on socket.io

Is there a way to retrieve the rooms associated with a socket in socket.io version 1.4? I attempted to use this.socket.adapter.rooms, but encountered an error in the chrome console: Cannot read property 'rooms' of undefined Here is the method I ...

javascriptnode.jssocket.io

Is there a way to remove specific mesh elements from a scene in Unity?

When I create multiple mesh objects with the same name, I encounter difficulties in selecting and removing them all from the scene. Despite attempting to traverse the function, I have not been successful in addressing the issue. event.preventDefault(); ...

javascriptthree.js

What is the best way to eliminate duplicate values within a v-for array?

To eliminate duplicate values, I wrote the following code: vue <div class="col-md-6" style="float: left"> <ul class="list-group"> <li class="list-group-item" :class="{ active: ind ...

javascriptvue.js

In a Java program, how could you arrange an array of Integers with three elements, so that the middle value is at the last index?

int[] numbers = new int[3]; numbers[0] = 3; Provided with a value to add into the array. I think this process will resemble insertion sort method utilizing - a while loop and an - if statement The last index is the middle value between index [0] & ...

javaarrayssortingwhile-loop

Utilize the arrow keys to navigate through the search suggestions

I am facing an issue with my search bar where I am unable to navigate through the suggestions using arrow keys. I have been struggling with this problem for days and would appreciate any help in resolving it. var searchIndex = ["404 Error", "Address Bar ...

javascriptjquerycsshtml

Flipping the switch to illuminate or darken a room

I am working on a project where I want to create a program that turns on a lightbulb when you click on it, and then turns it off when you click on it again. However, I am facing an issue where no matter which light I click on, the first one always turns ...

javascripthtml

Transmitting and receiving a blob using JavaScript

Is there a way to send a blob using a JQuery ajax request and receive it server-side with Node.js + express? I tried sending the blob as a JSON string, but it doesn't seem to include any of the binary data: {"type":"audio/wav","size":344108} Are th ...

javascriptjqueryajaxexpressblob

Setting the "status" of a queue: A step-by-step guide

I created a function to add a job to the queue with the following code: async addJob(someParameters: SomeParameters): Promise<void> { await this.saveToDb(someParameters); try { await this.jobQueue.add('job', ...

javascripttypescriptqueuetask-queuebull-queue

Show the Vue.js template in a Laravel Blade view

I have been struggling to integrate a Vue.js component into a Laravel blade file. Despite researching tutorials and Stack Overflow solutions, I have not been able to resolve the issue. Below is the template that I want to display: <template> < ...

javascriptphplaravelvue.js

A JavaScript object that performs a callback function

I am delving into learning node.js and experimenting with creating a new TCP Server connection. Check out the code snippet below: var server = require('net').createServer(function(socket) { console.log('new connection'); socket.se ...

javascriptnode.jscallback

Manipulating an object by inserting new properties using JavaScript and jQuery

I encountered an issue while working on instantiating an object that creates an associative array. Even after instantiation, I found that I was unable to add properties to the object's members because an error kept occurring. Let's take a look a ...

javascriptjqueryarraysobjectassociative-array

I have an HTML table with multiple cells containing inner HTML tables. I have implemented a function along with buttons to filter the main table, excluding the inner tables

My HTML Table is generated from my database, containing information about machines and their status pulled from emails with HTML Tables. Each row has a click option to open/hide the <td> tag showing the original table for more details and better trac ...

javascripthtmlhtml-table

Utilizing React SSR to dynamically import components based on API response

I am currently working on a SSR React app using the razzle tool, with the server running on the express framework. My goal is to dynamically load React components based on the value included in an API response. My folder structure looks like this: views ...

javascriptnode.jsreactjsexpressreact-router-v4