Java - Why can't I use charAt() to see if a char equals another?
Solution 1
if ( fieldNames.charAt(4) == 'f' )
because "f"
is a String
and fieldNames.charAt(4)
is a char
. you should use 'f'
for check char
"g" == "h"
works because both g and h are Strings
and you shouldn't use "g" == "h"
you should use "g".equals("h")
instead .
you can use == for primitive
data types like char,int,boolean
....etc.but for the objects
like String it's really different.
To know why read this
but you can use also
'g' == 'h'
you should wrap Strings by double quotation and char by single quotation
String s="g";
char c='g';
but char can only have one character but String can have more than one
String s="gg"; valid
char c='gg'; not valid
Solution 2
I was having the same problem, but I was able to solve it using:
if (str.substring(0,1).equals("x") )
the substring can be used in a loop str.substring(i, i + 1)
charAt(i).equals('x') will not work together
Mayron
Updated on July 10, 2022Comments
-
Mayron almost 2 years
I want to see if a character in my string equals a certain other char value but I do not know what the char in the string is so I have used this:
if ( fieldNames.charAt(4) == "f" )
But I get the error:
"Operator '==' cannot be applied to 'char', 'jav.lang.String'"
But
"g" == "h"
seems to work and I know you can use'=='
with char types.Is there another way to do this correctly? Thanks!