I have strings like this: `300.123,25` and after the comma I want to have always one digit. 

Expected result: `300.123,2`

Another issue would be to auto concatenate `,0` if the string does not have a comma

```
300.123  ->  300.123,0  

```

With the value from the input: 

```
value = value.toString().replace(/[^0-9\,]/g, "")
value = value.replace(/\B(?=(\d{3})+(?!\d))/g, ".")

```

I removed letters and other symbols. I've tried to check if I a have digits after comma with this: '(,\d)\d\*$'. But it doesn't work.