Check if a string contains only digits and white space in java Android

Question

I know this is a common way to ask but I just want to include white space when checking digits number, so I have this string

6031 3100 3440 0189 000

So now I want to check that value if it is contains just only the number

I came up with this solution

String Cardresult = edtCashCard.getText().toString();
if (Cardresult.matches("[0-9]+")){
   Toast.makeText(getApplicationContext(), "Good Job the strings are numbers", Toast.LENGTH_SHORT).show();

}
else{
   Toast.makeText(getApplicationContext(), "Error the string contains character", Toast.LENGTH_SHORT).show();
}

But now I know there's white space in the variable and based on the first condition, even though your variable contains numbers but since there's white space it does not count as a number it counts as string, and now I want to consider white space as a number to trigger to the first condition, is there anything that can I do with this? It very helpful me a lot

https://stackoverflow.com/questions/13973206/regex-for-field-that-allows-numbers-and-spaces — ADM, Sep 09 '21 at 06:47

Omkar · Accepted Answer · 2021-09-09T11:27:31.483

2

As @ADM suggested in comment you can update your regex [0-9]+ with below

[0-9 ]+

so it look like

 String Cardresult = edtCashCard.getText().toString();
    if (Cardresult.matches("[0-9 ]+")){
       Toast.makeText(getApplicationContext(), "Good Job the strings are numbers", Toast.LENGTH_SHORT).show();
    
    }
    else{
       Toast.makeText(getApplicationContext(), "Error the string contains character", Toast.LENGTH_SHORT).show();
    }

edited Sep 09 '21 at 11:27

answered Sep 09 '21 at 06:46

Omkar

3,040
1
22
42

Thanks `[0-9 ]` this is in my mind in the first place but I didn't try. – Henry Sep 09 '21 at 06:59
How on earth is trim going to work? – Scary Wombat Sep 09 '21 at 07:24
@ScaryWombat sry that was my bad, code updated plz check.... this may work – Omkar Sep 09 '21 at 07:30
`Cardresult.replace(" ","");` - this also will not work, Strings are immutable. – Scary Wombat Sep 09 '21 at 07:37

Check if a string contains only digits and white space in java Android

1 Answers1