How to add 2 letter in capital and numeric in textinput react native

Question

How to Add two capital alpha and 7 numeric value in textInput React native.

            <NumericTextInput
              label={'Pet License Number'}
              keyboardType="number-pad"
              // err1={errorData?.license ? true : false}
              value={license ? license : ''}
              mode={'outlined'}
              onChangeText={(val) => setLicense(val)}
              maxLength={9}
            />

This is the code and format is MD2345133

Answer 1

Try this regular expression that will helpful to validate input to only accept string with two capital alphabets and 7 numeric values:

^([A-Z]{2}\d{7})$

For example:

const App = () => {
  const [text, setText] = useState('');
  const [isValid, setIsValid] = useState();

  const handleChange = (event) => {
    const value = event.nativeEvent.text;
    const regex = /^[A-Z]{2}\d{7}$/;
    setText(value);
    if (regex.test(value)) {
      setIsValid(true);
    } else {
      setIsValid(false);
    }
  };

  return (
    <View>
      <TextInput
        placeholder="Enter two capital letters and 7 digits"
        onChange={handleChange}
        value={text}
      />
      {!isValid && <Text>Input string is not valid</Text>}
    </View>
  );
};