check if input is empty set to zero in javascript - Stack Overflow

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When the user delete the value in input using the backspace the function work correctly but if he delete the value and set a new number like 1 the new value is deleted and set again to zero.

<input type="text" id="txtField" value="0" ></input>

$(document).ready(function() {

  $("#txtField").keyup(function() {

    var v = $(this).val();

    console.log(v)
    if (v == "") {
      console.log(v)
      setTimeout(function() {
        $("#txtField").val(0);
      }, 1000);

    }
  });
});

I don't know what is the problem in my code any help please?

jsFiddle: /

When the user delete the value in input using the backspace the function work correctly but if he delete the value and set a new number like 1 the new value is deleted and set again to zero.

<input type="text" id="txtField" value="0" ></input>

$(document).ready(function() {

  $("#txtField").keyup(function() {

    var v = $(this).val();

    console.log(v)
    if (v == "") {
      console.log(v)
      setTimeout(function() {
        $("#txtField").val(0);
      }, 1000);

    }
  });
});

I don't know what is the problem in my code any help please?

jsFiddle: http://jsfiddle/2shadgtw/2/

• javascript

Share Improve this question Follow edited Dec 7, 2015 at 9:36 Praveen Kumar Purushothaman 167k2727 gold badges213213 silver badges260260 bronze badges asked Dec 7, 2015 at 9:29 SoraSora 2,5511919 gold badges7777 silver badges151151 bronze badges

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5 Answers 5

Sorted by: Reset to default 3

Don't use setTimeout. Instead try mapping with these three events:

$(document).ready(function() {
  $("#txtField").on("keyup change blur", function() {
    if ($(this).val().trim() == "")
      $(this).val(0);
  });
});

Fiddle: http://jsfiddle/5hm6e8hL/

I would use a blur event to do this rather than keyup:

$(document).ready(function() {
  $("#txtField").on("blur", function() {
    if (!$(this).val().trim())
      $(this).val(0);
  });
});

If the input is empty when it loses focus - then give it a value 0.

else - do nothing.

FIDDLE

The problem is that you have setTimeout. If the user clears the input and then enters a value in the next second, the function in setTimeout will still go off, setting the value to 0.

Try checking the input inside the setTimeout instead, like this:

JavaScript

$("#txtField").keyup(function() {
    setTimeout(function() {
        if ($("#txtField").val().trim().length === 0) {
            $("#txtField").val(0);
        }
    }, 1000);
});

JSFiddle

setTimeout is a bad solution. But ypu can use if-statement:

$(document).ready(function() {



 $("#txtField").keyup(function() {
var v = $(this).val();

console.log(v)
if (v == "") {
  console.log(v)
  setTimeout(function() {
    if(!$("#txtField").val()){
        $("#txtField").val(0);
    }
  }, 1000);

}


});
});

http://jsfiddle/guv0c5ox/

The best way to do this would be using focusout() function. Try this

<input type="text" id="txtField" value="0" />

$("#txtField").focusout(function() {

var v = $(this).val();

console.log(v)
if (v == "") {
    $("#txtField").val(0);
}
});

It will set the value to zero on focus out if the field is empty.

JSFIDDLE EXAMPLE

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