Using Input Text Validation

Users can configure Text Input fields to accept or restrict the type of data that recipients can enter based on a specific format, style, or number range. These validation settings are configured within the document preparation experience when sending out a signature request or creating, modifying, or utilizing a reusable template.

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Configuring text input validation

To configure the Text Input field validation settings within a signature request or reusable template:

1. Add a Text Input field to the request or template.
2. Select the Text Input field to configure field settings.
3. Click to expand the Validation section.
4. Select your validation option:
   • Predefined validation types: Choose from standard formats like numbers, email, dates, ZIP codes, or SSN.
   • Custom (Regular Expression): Create your own validation pattern for organization-specific requirements. See Custom (Regular Expression) validation for setup instructions and examples.

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Supported validation types

The following table lists the various supported validation for Text Input fields:

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Custom (Regular Expression) validation

Beyond the standard validation options, Box Sign offers a Custom (Regular Expression) option to customize validation for fields that need to meet requirements specific to your organization or region. Custom validation uses regular expressions (regex), which are sequences of characters that describe a specific pattern of allowed input for a field.

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Setting up custom validation

To configure custom validation:

1. Select Custom (Regular Expression) from the Validation dropdown menu.
2. Enter your regex pattern in the Regular Expression Pattern field. Provide an Error Message to display when the signer’s input is invalid.
3. (Recommended) Fill in the Field Name (Label) field to inform signers what data to populate in the field.

Make sure your regex pattern uses a valid and supported format. Otherwise, you won’t be able to apply the validation to the field. You might encounter two input errors: “Invalid pattern” if your regex pattern is invalid, or “Unsupported pattern” if your regex pattern is not supported by Box Sign guidelines. See Regex pattern requirements for supported syntax and limitations. When the signer enters data, the system checks it against your pattern. If the input doesn’t match, the field displays the error message you defined.

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Regex pattern requirements

To ensure your custom regex pattern works correctly, follow these guidelines: Supported characters:

• Unicode letters (\p{L})
• Unicode numbers (\p{N})
• Whitespace (\s)
• Common punctuation: - ( ) . , ' \ / @ _ : % ! ? ^
• Common international currency symbols: $ € £ ¥ ₹ ₩ ₽ ₺ ₫ ₴ ₱

Box Sign does not support the following regex patterns:

• Matching back references (\\[1-9])
• Nested quantifiers (++, **)
• Lookbehinds ((?<=, (?<!)
• Recursive and conditional checks ((?R), (?&))

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Example regex patterns

Below are useful examples of valid and supported regex patterns:

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Phone numbers

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Alphanumeric identifiers

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Other common patterns

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Known limitations

• Text input validation is not available for CFR Part 11 signature requests or templates.