JavaScript form Programming

A form of the way
1. Direct Positioning method
document.getElementById (ID);</br>
Document.getelementstagname (TagName);</br>
Document.getelementsbyname (name);</br>
2. Set Positioning method
Get Form Object
Mode 1
Console.log (document.forms[0].id);
Mode 2
Console.log (document.forms["MyForm"].id);
Mode 3
Console.log (document.forms.myform.id);
Mode 4
Console.log (document.myform.id);
# # # 3, directly through the name to get # # #
Document. " The value of name "</br>
Description: This method value is suitable for form operation, which belongs to the earlier usage, and the compatibility is better </br>

A reference to a FORM element
Get form elements
Length
Console.log (document.myform.elements.length);
Mode 1
Console.log (Document.myform.elements[0].value);
Mode 2
Console.log (document.myform.elements["username"].value);
Mode 3
Console.log (Document.myform.elements.username.value);
Mode 4
Console.log (Document.myform.username.value);


Properties: Whether to enable
Document.myform.username.disabled = true;
Method:
Document.myform.username.focus ();

JavaScript form Programming