You can use the pattern
attribute. The required
attribute is also needed, otherwise an input field with an empty value will be excluded from constraint validation.
<input pattern=".{3,}" required title="3 characters minimum">
<input pattern=".{5,10}" required title="5 to 10 characters">
If you want to create the option to use the pattern for "empty, or minimum length", you could do the following:
<input pattern=".{0}|.{5,10}" required title="Either 0 OR (5 to 10 chars)">
<input pattern=".{0}|.{8,}" required title="Either 0 OR (8 chars minimum)">
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…