How to set match password in react Js

Try this:

handleConfirmPassword = (event) => {
    if (event.target.value !== this.state.password) {
      message.error('error');
    }
}

You can also set your state like:

state = {
    password: '',
    confirmPassword: ''
}

And then, you can check the match on the handleConfirmPassword and on the submit.

handleConfirmPassword = (event) => {
    if (event.target.value !== this.state.password) {
      message.error('error');
      this.setState({confirmPassword: event.target.value})
    }
}

And then, a submit handler to the form:

handleSubmit = (event) => {
   if(this.state.password !== this.state.confirmPassword){
       message.error("The passwords doesn't match")
       return false; // The form won't submit
   }
   else return true; // The form will submit
}

import { useForm } from 'react-hook-form'

const { register, errors, handleSubmit, formState } = useForm({
    mode: "onChange"
  })

  const [newpassword, setNewPassword] = useState('')

  const [confirmpassword, setConfirmPassword] = useState('')

  const  { touched  } = formState;

  const onVerifyNewPassword = () => {

    if(touched.newpassword === true && touched.confirmpassword === true){
      if(newpassword !== confirmpassword){
        console.log('The passwords dont match')
        return
      }else{
        console.log('Ok.')
      }
   }
  }

              <form onSubmit={handleSubmit(onSubmit)}>
                <div className="input-group">
                  <label htmlFor="new">New Password</label>
                </div>
                <input type="newpassword"
                  ref={register({ required: true })}

                  name="newpassword"
                  onChange={(e) => setNewPassword(e.target.value)}
                  onBlur={onVerifyNewPassword}
                />
                <label htmlFor="new">Confirm Password</label>
                <input type="confirmpassword"
                  ref={register({ required: true })}
                  name="confirmpassword"
                  onChange={(e) => setConfirmPassword(e.target.value)}
                  onBlur={onVerifyNewPassword}



               />
                {/* <pre>{JSON.stringify(formState, null, 2)}</pre> */}


                <button><span>Change</span></button>

Assuming that both your password and confirmPassword are in state.

this.state = {
    password: '',
    confirmPassword: ''
}

handleSubmit = () => {
    const { password, confirmPassword } = this.state;
    // perform all neccassary validations
    if (password !== confirmPassword) {
        alert("Passwords don't match");
    } else {
        // make API call
    }
}

You can use password check callback:

checkPassword = (rule, value, callback) => {
  if (value && value !== form.getFieldValue('Password')) {
    callback("The passwords don't match");
  } else {
    callback();
  }
};

Thru validator rule:

<FormItem {...styles.formItemLayout} label="Password">
  {getFieldDecorator('Password', {
    rules: [{ required: true, message: 'Password is Required!' }],
  })(
    <Input
      name="password"
      type="password"
      value={password}
      style={styles.margin}
    />,
  )}
</FormItem>
<FormItem {...styles.formItemLayout} label="Confirm Password">
  {getFieldDecorator('ConfirmPassword', {
    rules: [
      { required: true, message: 'Confirm your Password!' }, 
      { validator: this.checkPassword }
    ],
  })(
    <Input
      name="password"
      type="password"
      style={styles.margin}
    />,
  )}
</FormItem>