INPUT - Input field

The INPUT tag is probably the most useful tag inside forms. It can generate buttons, input fields and checkboxes. In all cases, the NAME attribute must be set.

TYPE=text

This generates a input field, where the user can enter up to MAXLENGTH characters. The SIZE attribute lists the length of the input field (if the user enters more characters, the text will scroll). The VALUE attribute specifies the initial value for the input field.

TYPE=password

Same as TYPE=text, but the text will be hidden by "*" or similar characters. It is still sent in the clear to the server, though.

TYPE=checkbox

Produces a checkbox. It has two states, on and off. When it is on when the form is submitted, it will be sent as "name=on", otherwise it is ignored altogether. If you use CHECKED, it will come up checked (selected) initially.

TYPE=radio

Produces a radio button. A radio button always exists in a group. All members of this group should have the same NAME attribute, and different VALUEs. The VALUE of the selected radio button will be sent to the server. You must specify CHECKED on exactly one radio button, which then will come up selected initially.

TYPE=submit

Produces a button, which when pressed sends the contents of the form to the server. You can have more than one submit button in the form. Each should have a different NAME. The name and value of the pressed button will be sent to the server as well. The value of the VALUE attribute is typically used as text on the submit button.

TYPE=reset

Also produces a button, which will restore the form to its original state if pressed. The value of the VALUE attribute is typically used as text on the reset button.

TYPE=file

Allows the user to upload a file. It is still very new, so it is not very widely supported. It is typically presented as an input box with a button to start browsing the local hard disk. This way, a user can specify one or more filename(s) to upload.

TYPE=hidden

Allows you to embed information in the form which you do not want changed. This can be useful if the document is generated by a script and you need to store state information. NAME and VALUE of this input field will be sent to the server without modifications.

TYPE=image

Functions similar to a submit button, but uses an image instead. The ALIGN attribute controls the alignment of the image. The coordinates of the selected region will also be sent to the server, in the form of "NAME.x=n&NAME.y=n". A text browser will treat it as identical to a normal submit button.

Notes:

• Do not expect that if you set MAXLENGTH, you will get no more than so many characters. Anyone can modify his local copy of your form to enter as many characters as he wants.