How to delete last character from a input textbox using JavaScript? I make this small task Its function is that when we write a letter in the input, it checks the index number of the value in the queue. And we will choose them all And we will select everyone in the input except the letter we have written.

1. Now I want that when I delete a letter, it will be deleted and the getSelectedText function will be run.
2. And when I press the control button or any other Esc key. So let's show all the values in the Array.

HTML Code:

<input id="autocomplet" onkeyup="filter(this.value);">

Javascript Code:

<script>
var data = document.querySelector('#autocomplet');
var myArray = ["c  ", "java", "php", "coldfusion", "javascript", "asp", "ruby"];

function filter(letter) {
        var results = [];
        var len = myArray.length;
  for (var i = 0; i < len; i  ) {
    if (myArray[i].indexOf(letter) == 0){
       results.push(myArray[i]);
       data.value = results;
       getSelectedText(data,letter);
    }
  }
if((event.keyCode == 46) || (event.keyCode == 8)){
        data.value='';
    }
}
function getSelectedText(data,letter) {
  data = data.value;
  var datalength = data.length; 
  var letterlength = letter.length;
  autocomplet.setSelectionRange(letterlength,datalength);
}
</script>

CodePudding user response：

I don't Know If This Helps but here it is.

    var data = document.querySelector('#autocomplet');
    var myArray = ["c  ", "java", "php", "coldfusion", "javascript", "asp", "ruby"];

    function filter(letter) {
        var results = [];
        var len = myArray.length;
        if ((event.keyCode == 46) || (event.keyCode == 8)) {
            return getSelectedText(data, letter);
            // data.value = '';
        }
        for (var i = 0; i < len; i  ) {
            if (myArray[i].indexOf(letter) == 0) {
                results.push(myArray[i]);
                data.value = results;
                getSelectedText(data, letter);
            }
        }
    }

    function getSelectedText(data, letter) {
        data = data.value;
        var datalength = data.length;
        var letterlength = letter.length;
        autocomplet.setSelectionRange(letterlength, datalength);
    }

CodePudding user response：

Consider the following. This is a jQuery example, yet all the same algorithm should apply to JavaScript.

$(function() {
  var myArray = ["c  ", "java", "php", "coldfusion", "javascript", "asp", "ruby"];

  function checkEntry(event) {
    console.log(event.keyCode);
    if (event.keyCode == 8) {
      resetVal(event.target);
    }
    filter($(event.target).val(), event.target);
  }

  function resetVal(target) {
    var val = $(target).val();
    var sel = window.getSelection().toString();
    window.getSelection().empty();
    console.log("Reset", val, sel);
    $(target).val(val.slice(0, val.length - 1));
  }

  function filter(term, target) {
    var result;
    var notFound = true;
    console.log("Filter", term);
    $.each(myArray, function(i, v) {
      if (v.indexOf(term) == 0 && notFound) {
        result = v;
        notFound = false;
      }
    });
    $(target).val(result);
    getSelectedText(result, term);
  }

  function getSelectedText(data, letter) {
    console.log("Select", data, letter);
    $("#autocomplet").get(0).setSelectionRange(letter.length, data.length);
  }

  $("#autocomplet").keyup(checkEntry);
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input id="autocomplet" type="text" />

CodePudding user response：

You can take the input and put it in a string. Then take the lenght of the input and do a for loop which will run one time less than the number of the lenght. After that get letter by letter to reconstruct the phrase in a new variable.

let phrase = “your_phrase.”;
let x = 0;
let p2=“”;
let n = 0;
while(true)
{
   if(phrase == null){break;}
   x  
}
x—-; //maybe try to delete this if 1 extra letter deleted.
for(n; n <= x-1;x  )
{
   p2 = p2 - phrase[n];
}