useKeyFilter used to block individual keystrokes based on a pattern.
import { useKeyFilter } from '@primereact/hooks';const keyfilter = useKeyFilter();useKeyFilter provides various presets configured with the pattern option.
'use client';
import { useKeyFilter } from '@primereact/hooks';
import { InputText } from 'primereact/inputtext';
import { Label } from 'primereact/label';
import * as React from 'react';
export default function PatternDemo() {
const { onKeyPress: onIntegerKeyPress } = useKeyFilter({ pattern: 'int' });
const { onKeyPress: onNumberKeyPress } = useKeyFilter({ pattern: 'num' });
const { onKeyPress: onMoneyKeyPress } = useKeyFilter({ pattern: 'money' });
const { onKeyPress: onHexKeyPress } = useKeyFilter({ pattern: 'hex' });
const { onKeyPress: onAlphaKeyPress } = useKeyFilter({ pattern: 'alpha' });
const { onKeyPress: onAlphanumKeyPress } = useKeyFilter({ pattern: 'alphanum' });
const [integer, setInteger] = React.useState('');
const [number, setNumber] = React.useState('');
const [money, setMoney] = React.useState('');
const [hex, setHex] = React.useState('');
const [alphabetic, setAlphabetic] = React.useState('');
const [alphanumeric, setAlphanumeric] = React.useState('');
return (
<div>
<div className="flex flex-wrap gap-3 mb-4">
<div className="flex-auto">
<Label htmlFor="integer" className="font-bold block mb-2">
Integer
</Label>
<InputText
id="integer"
value={integer}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setInteger(e.target.value)}
onKeyPress={onIntegerKeyPress}
className="w-full"
/>
</div>
<div className="flex-auto">
<Label htmlFor="number" className="font-bold block mb-2">
Number
</Label>
<InputText
id="number"
value={number}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setNumber(e.target.value)}
onKeyPress={onNumberKeyPress}
className="w-full"
/>
</div>
<div className="flex-auto">
<Label htmlFor="money" className="font-bold block mb-2">
Money
</Label>
<InputText
id="money"
value={money}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setMoney(e.target.value)}
onKeyPress={onMoneyKeyPress}
className="w-full"
/>
</div>
</div>
<div className="flex flex-wrap gap-3">
<div className="flex-auto">
<Label htmlFor="hex" className="font-bold block mb-2">
Hex
</Label>
<InputText
id="hex"
value={hex}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setHex(e.target.value)}
onKeyPress={onHexKeyPress}
className="w-full"
/>
</div>
<div className="flex-auto">
<Label htmlFor="alphabetic" className="font-bold block mb-2">
Alphabetic
</Label>
<InputText
id="alphabetic"
value={alphabetic}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setAlphabetic(e.target.value)}
onKeyPress={onAlphaKeyPress}
className="w-full"
/>
</div>
<div className="flex-auto">
<Label htmlFor="alphanumeric" className="font-bold block mb-2">
Alphanumeric
</Label>
<InputText
id="alphanumeric"
value={alphanumeric}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setAlphanumeric(e.target.value)}
onKeyPress={onAlphanumKeyPress}
className="w-full"
/>
</div>
</div>
</div>
);
}
In addition to the presets, a regular expression can be configured for customization of blocking a single key press.
'use client';
import { useKeyFilter } from '@primereact/hooks';
import { InputText } from 'primereact/inputtext';
import { Label } from 'primereact/label';
import * as React from 'react';
export default function RegexDemo() {
const { onKeyPress: onSpaceKeyPress } = useKeyFilter({ pattern: /[^\s]/ });
const { onKeyPress: onCharsKeyPress } = useKeyFilter({ pattern: /^[^<>*!]+$/ });
const [spacekey, setSpacekey] = React.useState('');
const [chars, setChars] = React.useState('');
return (
<div>
<div className="flex flex-wrap gap-3">
<div className="flex-auto">
<Label for="spacekey" className="font-bold block mb-2">
Block Space
</Label>
<InputText
id="spacekey"
value={spacekey}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setSpacekey(e.target.value)}
onKeyPress={onSpaceKeyPress}
fluid
/>
</div>
<div className="flex-auto">
<Label htmlFor="chars" className="font-bold block mb-2">
Block < > * !
</Label>
<InputText
id="chars"
value={chars}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => setChars(e.target.value)}
onKeyPress={onCharsKeyPress}
fluid
/>
</div>
</div>
</div>
);
}
In addition to the presets, a regular expression can be used to validate the entire word using validateOnly option.
'use client';
import { useKeyFilter } from '@primereact/hooks';
import { InputText } from 'primereact/inputtext';
import { Label } from 'primereact/label';
import * as React from 'react';
export default function RegexWordDemo() {
const { onKeyPress, validate } = useKeyFilter({ pattern: /^[+]?(\d{1,12})?$/, validateOnly: true });
const [text, setText] = React.useState('');
const validateInput = (e: React.ChangeEvent<HTMLInputElement>) => {
if (validate(e)) {
setText(e.target.value);
}
};
return (
<div className="flex justify-center">
<div>
<Label htmlFor="numkeys" className="font-bold block mb-2">
Block Numeric (allow "+" only once at start)
</Label>
<InputText
id="numkeys"
value={text}
onChange={(e: React.ChangeEvent<HTMLInputElement>) => validateInput(e)}
onKeyPress={onKeyPress}
fluid
/>
</div>
</div>
);
}