HTML tutorial
CSS3 tutorial
Bootstrap tutorial
JavaScript tutorial
JQuery tutorial
AngularJS tutorial
React tutorial
NodeJS tutorial
PHP tutorial
Python tutorial
Python3 tutorial
Django tutorial
Linux tutorial
Docker tutorial
Ruby tutorial
Java tutorial
C tutorial
C ++ tutorial
Perl tutorial
JSP tutorial
Lua tutorial
Scala tutorial
Go tutorial
ASP.NET tutorial
C # tutorial
Input Text Object : Change the value of a text field
The value property sets or returns the value of the value attribute of a text field.
The value property contains the default value OR the value a user types in (or a value set by a script).
Property | |||||
---|---|---|---|---|---|
value | Yes | Yes | Yes | Yes | Yes |
Return the value property:
Set the value property:
Value | Description |
---|---|
text | Specifies the value of the input text field |
Return Value: | A String, representing the value of the text field |
---|
Get the value of a text field:
var x = document.getElementById("myText").value;
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;
}
Dropdown list in a form:
var mylist = document.getElementById("myList");
document.getElementById("favorite").value = mylist.options[mylist.selectedIndex].text;
Another 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;
An example that shows the difference between the defaultValue and value property:
var x = document.getElementById("myText");
var defaultVal = x.defaultValue;
var currentVal = x.value;
HTML reference: HTML <input> value attribute
❮ Input Text Object