How to Dynamically Create Variables

JavaScript: Dynamically Creating Variables for Loops

You should use an array:

function createVariables(){
  var accounts = [];

  for (var i = 0; i <= 20; ++i) {
      accounts[i] = "whatever";
  }

  return accounts;
}

You then have access to accounts[0] through accounts[20].

How can you dynamically create variables?

Unless there is an overwhelming need to create a mess of variable names, I would just use a dictionary, where you can dynamically create the key names and associate a value to each.

a = {}
k = 0
while k < 10:
    # dynamically create key
    key = ...
    # calculate value
    value = ...
    a[key] = value 
    k += 1

There are also some interesting data structures in the collections module that might be applicable.

Dynamically creating a variable

In python we tend to avoid this kind of dynamic variables, but anyway your answer is:

a = 'test'
globals()[a] = 123
print(test)

Better approach is by using a dictionnary.

a = 'test'
myVar = {}
myVar[a] = 123
print(myVar['test'])

Is it a good idea to dynamically create variables?

I think it's preferable to use a dictionnary if it's possible:

vars_dict = {}
vars_dict["my_variable"] = 'Some Value'
vars_dict["my_variable2"] = 'Some Value'

I think it's more pythonic.

How to create variables dynamically in Java?

A Map allows you to relate any key with any value. In this case, the key is the name of the variable, and the value is the value

Map<String, String> details = new HashMap<>();
for (int i = 1; i <101; i++) {
    if (i<60) {
        details.put("person" + i, "female");
    }
    else {
        details.put("person" + i, "male");
    }
}

How to dynamically create variable with loop?

You need to give the emails a name to submit them

Also I removed the onsubmit form the submit button. It does not belong there and can be removed. You have a submit event handler and that should do it

const container = document.getElementById("container");
document.getElementById("nameForm").addEventListener("submit", tableGen);
document.getElementById("okButton").addEventListener("click", emailGen);


//fuction to genrate email field
function emailGen() {
  const quant = document.getElementById("quantity").value;
  while (container.hasChildNodes()) {
    container.removeChild(container.lastChild);
  }
  for (let i = 0; i < quant; i++) {
    var emailGen = document.createElement("input");
    emailGen.type = "email";
    emailGen.id = "email" + i;
    emailGen.name = "email" + i;
    emailGen.placeholder = "Member's Email";
    container.appendChild(emailGen);
  }
}


//function for table generator
function tableGen(e) {
  e.preventDefault();
  const body = document.querySelector("body");
  const table = document.createElement("table");
  const tblbody = document.createElement("tbody");
  const input1 = document.getElementById("input1").value;
  const quan = document.getElementById("quantity").value;

  const emails = container.querySelectorAll("[type=email]")

  console.log(emails.length)

  //table rows loop
  for (let i = 0; i < quan; i++) {
    const tblrow = document.createElement("tr");
    for (let j = 0; j < emails.length; j++) {
      const tblcell = document.createElement("td");
      //table column loop
      const pname = document.createTextNode(input1);
      tblcell.appendChild(pname);
      const tname = document.createTextNode(emails[j].value);
      tblcell.appendChild(tname);
      tblrow.appendChild(tblcell);
    }


    tblbody.appendChild(tblrow);

  }
  console.log
  table.appendChild(tblbody);
  body.appendChild(table);
  table.setAttribute("border", "4");
}

<form id="nameForm">
  <input type="text" id="input1" placeholder="Name"><br/>
  <input type="number" id="quantity" name="quantity" placeholder="Total Members(max 10)" min="1" max="10">
  <button type="button" id="okButton">OK</button>
  <div id="container"></div>
  <br/>
  <input type="submit" value="submit">
</form>

how to Dynamically generate different variables in Angular?

define a variable type array of boolean and use in the table.

check:boolean[]=[]; //<--see that you equal to an array

I suppose you has some like

<tr *ngFor="let item of listItems;let i=index">
<td>{{item.invoiceAmmount}}</td>
...
<td><input type="checkbox" [(ngModel)]="check[i]"></td>
</tr>

Then you can use a getter to total

get total()
{
   let total=0;
   this.listItems.forEach((x,index)=>{
     if (check[index])
         total+=x.invoiceAmmount;
   })
   return total;
}

And in your .html

Total:{{total}}
<div *ngIf="total>max_ammount">You has execeded tha ammout!</div>

NOTE: If you dont want use a getter you can use

<td><input type="checkbox" [ngModel]="check[i]"
                           (ngModelChange)="check[i]=$event;getTotal()">
</td>

getTotal()  //<--your function getTotal
{
       let total=0;
       this.listItems.forEach((x,index)=>{
         if (check[index])
             total+=x.invoiceAmmount;
       })
       this.total=total //<--store the total in a variable "total"
}

How do I create dynamic variable names inside a loop?

Use an array for this.

var markers = [];
for (var i = 0; i < coords.length; ++i) {
    markers[i] = "some stuff";
}