How to do null/empty check of a String inside a TextFormField validator function in dart/flutter?-CodePudding

Is there a shorter way to check if a string is either null or empty? Do I need to write every time 2 conditions inside if to check it?

validator: (value) {
    if (value == null || value.isEmpty){
        //....
    }
}

In python we can do if value and it works. In javascript we could do if(!value).

CodePudding user response：

As from my understanding, the TextEditingController use TextEditingValue.empty which is providing empty string initially. I am not able to get null exception.

I think we can use ! while we are sure the value is empty, not null.

validator: (value) {
  if (value!.isEmpty) return "Empty";

I always prefer checking null first, for nullable data type.

CodePudding user response：

try this

validator: (value) {
if (value.isNotEmpty){
     print(value);
 }else{
   print("Empty");
 }
}