Returns the index within this string of the last occurrence of
the specified character, searching backward starting at the
specified index. For values of ch
in the range
from 0 to 0xFFFF (inclusive), the index returned is the largest
value k such that:
is true. For other values of(this.charAt(k) == ch) && (k <= fromIndex)
ch
, it is the
largest value k such that:
is true. In either case, if no such character occurs in this string at or before position(this.codePointAt(k) == ch) && (k <= fromIndex)
fromIndex
, then
-1
is returned.
All indices are specified in char
values
(Unicode code units).
ch | a character (Unicode code point). | |
fromIndex | the index to start the search from. There is no
restriction on the value of fromIndex . If it is
greater than or equal to the length of this string, it has
the same effect as if it were equal to one less than the
length of this string: this entire string may be searched.
If it is negative, it has the same effect as if it were -1:
-1 is returned. |
fromIndex
, or -1
if the character does not occur before that point.
Diagram: String