Code for validating login textbox in
Input errors, such as an incorrect email address, will be indicated using the web browser dialogs as in the previous example.attribute allows the use of regular expressions to specify custom formats for the input.In addition to providing instructions, validate user input to help users avoid mistakes.
Most current web browsers support this attribute and will communicate missing required input to the user, using standard web browser dialog mechanisms.
Note that the label also displays “(required)”, to inform users that don’t use assistive technology or use older web browsers that do not support the HTML5 attribute informs assistive technologies about required controls so that they are appropriately announced to the users (as opposed to validating the input).
Most current web browsers automatically set its value to .
These dialogs are expected to respect the settings and preferences of the user in the web browser (and operating system), such as default font-size, colors, and language.
In the example below, the attribute is added to the input field.
Where possible, require user confirmation for irreversible actions, such as permanent deletion of data.