JavaScript form validation items to note _javascript tips

JavaScript form Programming:

How to find a FORM element:

1.var Oform=document.getelementbyid ("Form1");

2.var oform=document.forms[form1]//through name lookup;

Two. Common features of form fields:

Disabled: This property is used to indicate whether a form control is available;

Form property: This property returns the form that contains the field;

Blur (): This method causes form fields to lose focus;

Focus (): This method causes the form field to be focused;

Blur event: When a form field loses focus, the event occurs, and then the onblur event handler is executed;

Focus Event: Occurs when the form field is focused, and then executes the onfocus event handler;

Third: Form submission, resetting

Sumbit:oform Sumbit ();

Reset:oform Reset ();

Four. Get the value of the text box:

Length otext.value.length;

Five: Add element node, text node, delete element

Createlement,creattextnode,remove;

Six: Select the value of the check box: Select

Seven: Form validation Best Practices:

Must be helpful to the user;

Don't let people hate you;

Use HTML instead of JavaScript whenever possible

Show all errors at once;

Catch errors early;

Don't be too strict if you are unsure;