Input Text value attribute

HTML DOM Input Text Obheto

Definition and usage

value Attribute setting or returning the value of the text field's value attribute.

The HTML value attribute contains a default value or a value entered by the user (or a value set by the script).

See also:

HTML Reference Manual:HTML <input> value 属性

Instance

Example 1

Change the value of the text field:

document.getElementById("myText").value = "Bill Gates";

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More examples are provided below the page.

Syntax

Return the value attribute:

textObject.value

Set the value attribute:

textObject.value = text

Attribute value

Value Description
text Specify the value of the input text field.

Technical details

Return value: String value, representing the value of the text field.

More examples

Halimbawa 2

Get the value of the text field:

var x = document.getElementById("myText").value;

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Halimbawa 3

Form validation:

var at = document.getElementById("email").value.indexOf("@");
var age = document.getElementById("age").value;
var fname = document.getElementById("fname").value;
submitOK = "true";
if (fname.length > 10) {
  alert("The name may have no more than 10 characters");
  submitOK = "false";

if (isNaN(age) || age < 1 || age > 100) {
  alert("The age must be a number between 1 and 100");
  submitOK = "false";

if (at == -1) {
  alert("Not a valid e-mail!");
  submitOK = "false";

if (submitOK == "false") {
  return false;

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Halimbawa 4

Dropdown list sa form:

var mylist = document.getElementById("myList");
document.getElementById("favorite").value = mylist.options[mylist.selectedIndex].text;

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Halimbawa 5

Ibang dropdown list:

var no = document.getElementById("no");
var option = no.options[no.selectedIndex].text;
var txt = document.getElementById("result").value;
txt = txt + option;
document.getElementById("result").value = txt;

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Halimbawa 6

Ipinapakita ang halimbawa ng pagkakaiba sa pagitan ng mga attribute na defaultValue at value:

var x = document.getElementById("myText");
var defaultVal = x.defaultValue;
var currentVal = x.value;

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浏览器支持

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Chrome Edge Firefox Safari Opera
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HTML DOM Input Text Obheto