JavaScript form Programming:
I. How to find form elements:
1.var Oform=document.getelementbyid ("Form1");
2.var oform=document.forms[form1]//is searched by name;
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 containing the field;
Blur (): This method causes the form field to lose focus;
Focus (): This method causes the form field to get focus;
Blur event: Occurs when the form field loses focus, and then executes the onblur event handler;
Focus Event: The event occurs when the form field receives focus, followed by the onfocus event handler;
Three: Form submission, reset
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;
JavaScript Forms Validation Knowledge