很简单的,就是想分割一个文件路径字符串,取它的扩展名。
String file=new String("c:\\test\\file.exe");
String[] temp = file.split(".");
程序运行到这里,就异常终止了。想想以前用split分割很多种符号,都没问题。随手试了试split("\\"),依然失败。又换了其他的各种符号":"、"##"等等却又没问题。难道"."和"\\"有什么不对么?
在仔细看看JDK的文档:
String[] java.lang.String.split(String regex)
split
public String[] split(String regex)
Splits this string around matches of the given regular expression.
This method works as if by invoking the two-argument split method with the given expression and a limit argument of zero. Trailing empty strings are therefore not included in the resulting array.
The string "boo:and:foo", for example, yields the following results with these expressions:
Regex Result
: { "boo", "and", "foo" }
o { "b", "", ":and:f" }
Parameters:
regex - the delimiting regular expression
Returns:
the array of strings computed by splitting this string around matches of the given regular expression
Throws:
PatternSyntaxException - if the regular expression's syntax is invalid
Since:
1.4
See Also:
Pattern
清清楚楚的写着参数是String regex,一个regular expression,正则表达式。哎,以前没认真看过,一直当成普通的字符串在用了,只是运气好,恰好没出错。知错就改:
改成String[] temp = file.split("\\.");或者String[] temp = file.split("[.]");就可以了。至于那个"\\"分割的话,用String[] temp = file.split("\\\\");就可以了。