Cannot extract phone number input from custom made field using Formik

问题

I have a custom input field for the phone number made from the library 'react-phone-input-2',

I will show the code for the custom input field made by a colleague

<PhoneInput
      inputProps={{
        name: inputName,
      }}
      country="lb"
      value={phoneNumber}
      placeholder="1234456"
      onChange={phone => handleInputChange(inputName, phone)}
      buttonClass="buttonarrow"
      containerStyle={mainContainer}
      inputStyle={phoneInput(countryCodeBtnWidth, isMobileScreen, hasError)}
      buttonStyle={countryCodeBtn(countryCodeBtnWidth, isMobileScreen)}
      dropdownStyle={dropDownList}
    />

When I import this and try to send formik to handle the handleInputOnChange I am not able to extract the values even though all other fields are being extracted in the same way.

I will post code for the extraction

<PhoneInputValidation
                name="phoneNumber"
                value={formik.phoneNumber}
                handleInputChange={formik.handleChange}
                hasError={
                  formik.errors.phoneNumber && formik.touched.phoneNumber
                }
                validationMessage={ERROR_REQUIRED}
                onBlur={formik.handleBlur}
              />

phoneInputValidation is another component made from importing phoneInput the code is below

<ValidationModule hasError={hasError} validationMessage={validationMessage}>
    <PhoneInputCustom
      handleInputChange={handleInputChange}
      hasError={hasError}
      inputName={name}
      phoneNumber={value}
    />
  </ValidationModule>

ps: using formik.handleChange on other fields in the same form is working fine

回答1:

Formik's handleChange accepts 2 types of arguments:

Field name [string]: in this case it returns a functions to which you can pass the change event or value directly
Change event: in this case it will get the name of the field to update from the change event itself

https://github.com/jaredpalmer/formik/blob/d4049f2da7e2e8811b498ea8013b77af063c6c8a/packages/formik/src/Formik.tsx#L657-L667

Your code only uses the first form:

<PhoneInput
      ...
      onChange={phone => handleInputChange(inputName, phone)}
      ...
    />

Formik will ignore the phone value in this case. Following samples should work.

<PhoneInput
      ...
      onChange={phone => handleInputChange(inputName)(phone)}
      ...
    />

<PhoneInput
      ...
      onChange={phone => handleInputChange({ 
        target: { 
          name: inputName
          value: phone 
        }
      })}
      ...
    />

Also have a look at the documentation of the phone input as it gives more data with the change event than only the phone number:

https://github.com/bl00mber/react-phone-input-2#events

来源：https://stackoverflow.com/questions/61222416/cannot-extract-phone-number-input-from-custom-made-field-using-formik

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reactjs

formik