Validating user input visual basic
Google makes extensive use of phone numbers in its cloud applications, business operations, and in the Android, Chrome, and (presumably) Fuchsia operating systems.
Handling phone numbers effectively is important for security and ease of use in all these software systems.
To help Android and other application developers answer the question "Is this a valid telephone number?
" more easily, Google developed and helps maintain an open source Java, C , and Java Script library for "parsing, formatting, and validating international phone numbers", libphonenumber.
If there are multiple validation controls on the form, the Is Valid property provides a convenient way to check for any input errors.
If you run this example, and submit the form without making an entry in the age field, you should see the result shown in figure 8.11.
The Web Forms infrastructure provides a selection of validation controls that you can use to validate user input, and display error messages to the user.
If VB script, please advise on logic Now select your Data Entry form and from the image drop down list add on a Preview of Template below the Length entry field and make this image as large as possible so the users will see the warning clearly.
As the operators type in the value then both typed in value and the warning message will appear on the preview below as they type it, so if they are adding in 11 when they type the 1st 1 the warning will be displayed but this will disappear when the 2nd character is entered.
In this example, we have redundancy for illustration purposes.
We use the Required Field Validator to ensure that the user makes an entry in the age-Text Box, while the Regular Expression Validator requires the entry to consist of 1 to 3 digits: validation Expression="^\d$" Finally, we use a Range Validator to ensure that the user be between 1 and 12 0 years of age: type="Integer" minimum Value="1" maximum Value="12 0" Note that the following properties are common to all three controls: • control To Validate—Specifies the control to be validated. • error Message—The error text to be displayed if validation fails.