拆分Java String返回空数组？ [重复]

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Split string with dot as delimiter 10 answers
用点作为分隔符10的分裂字符串答案

I have a String something like this

我有一个像这样的字符串

"myValue"."Folder"."FolderCentury";

I want to split from dot("."). I was trying with the below code:

我想从点（“。”）拆分。我正在尝试使用以下代码：

String a = column.replace("\"", "");
String columnArray[] = a.split(".");

But columnArray is coming empty. What I am doing wrong here?

但是columnArray将变空。我在这做错了什么？

I will want to add one more thing here someone its possible String array object will contain spitted value like mentioned below only two object rather than three.?

我想在这里再添加一个东西，其可能的String数组对象将包含spitted值，如下面提到的只有两个对象而不是三个。？

columnArray[0]= "myValue"."Folder";
columnArray[1]= "FolderCentury";

5 个解决方案

#1

Note that String#split takes a regex.

请注意，String＃split采用正则表达式。

You need to escape the special char . (That means "Any character"):

你需要逃避特殊的字符。（这意味着“任何角色”）：

 String columnArray[] = a.split("\\.");

(Escaping a regex is done by \, but in Java, \ is written as \\).

（转义正则表达式由\完成，但在Java中，\写为\\）。

You can also use Pattern#quote:

你也可以使用Pattern＃quote：

Returns a literal pattern String for the specified String.

返回指定String的文字模式String。

String columnArray[] = a.split(Pattern.quote("."));

String columnArray [] = a.split（Pattern.quote（“。”））;

By escaping the regex, you tell the compiler to treat the . as the String . and not the special char ..

通过转义正则表达式，您告诉编译器处理。作为字符串。而不是特殊的炭..

#2

You must escape the dot.

你必须逃脱点。

String columnArray[] = a.split("\\.");

#3

split() accepts an regular expression. So you need to skip '.' to not consider it as a regex meta character.

split（）接受正则表达式。所以你需要跳过'。'不要将它视为正则表达式元字符。

String[] columnArray = a.split("\\.");

#4

While using special characters need to use the particular escape sequence with it.

使用特殊字符时需要使用特定的转义序列。

'.' is a special character so need to use escape sequence before '.' like:

''是一个特殊字符，所以需要在'。'之前使用转义序列。喜欢：

 String columnArray[] = a.split("\\.");

#5

The next code:

下一个代码：

   String input = "myValue.Folder.FolderCentury";
   String regex = "(?!(.+\\.))\\.";
   String[] result=input.split(regex);
   System.out.println(Arrays.toString(result));

Produces the required output:

产生所需的输出：

[myValue.Folder, FolderCentury]

The regular Expression tweaks a little with negative look-ahead (this (?!) part), so it will only match the last dot on a String with more than one dot.

正则表达式稍微调整一下，使用负向前瞻（这个（？！）部分），因此它只匹配具有多个点的字符串上的最后一个点。

#1