逗号分隔数据 [英] Separate Data by Comma

问题描述

我正在学习RegEx。完全是新手：P

I am learning RegEx. completely a newbie :P

我想从下面的数据中分离数字，这些数据仅用逗号分隔

I wanted to separate numbers from the below data, which are separated by comma only

test
t,b
45,49
31,34,38,34,56,23,,,,3,23,23653,3875,3.7,8.5,2.5,7.8,2., 6 6 6 6 ,
,
.
.,/;,jm.m.,,n ,sdsd, 3,2m54,2 4,2m,ar ,SSD A,,B,4D,CE,S4,D,2343ES,SD

假设我从表单文本字段中获取了上述数据。现在，我只想读取以逗号分隔的数字

Suppose I am getting the above data from Form text field. Now I want to read the data only which are numbers seperated by comma

解决方案应该是[string]

Solution should be[string]

45,49,31,34,38,34,56,23,3,23,23653,3875

所有其他数据都应跳过。
我尝试了类似^ [0-9] + \，$

all other data should be skipped. I tried something like this ^[0-9]+\,$

的方法，但是它也在3.7中选择了7，在8.5中选择了5，依此类推。 ....

But it's also selecting 7 from 3.7, and 5 from 8.5, etc.....

有人可以帮我解决这个问题吗！

Can anyone help me out in solving this!!

推荐答案

假设您已经在逗号之间分割，并尝试检查获取的元素是否为数字，请使用以下表达式： ^ \d +（?: \.\d +）？$ ，这意味着：必须以数字开头，后接一个点和至少一个数字。

Assuming you are already splitting at commas and try to check whether the elements you get are numbers, use this expression: ^\d+(?:\.\d+)?$, which means: "must begin with digits potentially followed by a dot and at least one more digit".

这将匹配 31 和 7.8 ，但不是 2。， 6 6 6 6 或 2m54 。

This would match 31 as well as 7.8, but not 2., 6 6 6 6 or 2m54.

下面是该表达式的部分解释：

Here's a part by part explanation of that expression:

• ^ 表示：比赛必须从第一个字符开始


• $ 表示：比赛必须在最后一个字符处结束，因此两者都意味着整个字符串必须匹配


• \d + 表示：一个或多个数字


• （?: ...）是一个非捕获组，允许应用？量词


• \。表示：文字点


• （?: \.\d +）？的意思是：点的零次或一次出现，后跟至少一位数字

• ^ means: matches must start at the first character
• $ means: matches must end at the last character, so both together mean the entire string must match
• \d+ means: one or more digits
• (?: ... ) is a non-capturing group allowing to apply the ? quantifier
• \. means: the literal dot
• (?:\.\d+)? thus means: zero or one occurences of a dot followed by at least one digit

编辑：如果只需要整数，则删除组： ^ \d + $ ->整个输入必须为1或

if you only want integer numbers, just remove the group: ^\d+$ -> entire input must be one or more digits.

编辑2：如果可以添加和添加输入字符串的逗号（请参见编辑4），您应该可以使用此正则表达式获取所有数字：（？< =，）\s *（\d + （？：\.\d +）？）\s *（？=，）（仅整数会要求您删除（?: \.＼ ＼d +）？部分）。

Edit 2: If you can prepend and append a comma to the input string(see Edit 4), you should be able to use this regex for getting all numbers: (?<=,)\s*(\d+(?:\.\d+)?)\s*(?=,) (integers only would require you to remove the (?:\.\d+)? part).

该表达式获取两个逗号之间的所有数字，并且逗号和数字之间可能存在空格，并将该数字分组。这样可以防止匹配 6 6 6 6 或 2m54 。然后，只需遍历所有匹配项即可。

That expression gets all numbers between two commas with possible whitespace between the commas and the number and catches the number into a group. This should prevent matches of 6 6 6 6 or 2m54. Then just iterate over the matches to get all the groups.

编辑3：下面是输入字符串的示例。

Edit 3: Here's an example with your input string.

String input = "test\n" +
        "t,b\n" +
        "45,49\n" +
        "31,34,38,34,56,23,,,,3,23,23653,3875,3.7,8.5,2.5,7.8,2., 6 6 6 6 ,\n" +
        ",\n" +
        ".\n" +
        ".,/;,jm.m.,,n ,sdsd, 3,2m54,2 4,2m,ar ,SSD A,,B,4D,CE,S4,D,2343ES,SD\n";

Pattern p = Pattern.compile( "(?<=,|\\n)\\s*(\\d+(?:\\.\\d+)?)\\s*(?=,|\\n)" );    

Matcher m = p.matcher( input );

List<String> numbers = new ArrayList<String>();

while(m.find())
{
  numbers.add( m.group( 1 ) );
}

System.out.println(Arrays.toString( numbers.toArray() ));

//prints: [45, 49, 31, 34, 38, 34, 56, 23, 3, 23, 23653, 3875, 3.7, 8.5, 2.5, 7.8, 3]
//removing the faction group: [45, 49, 31, 34, 38, 34, 56, 23, 3, 23, 23653, 3875, 3]

编辑4：实际上，您不需要添加逗号，只需使用以下表达式：

Edit 4: actually, you don't need to add commas, just use this expression:

`(?<=,|\n|^)\s*(\d+)\s*(?=,|\n|$)`

开头和结尾处的组表示匹配必须跟随输入的开头，逗号或换行符，以及输入的末尾是逗号或换行符。

The groups at the start and end mean the match must follow the start of the input, a comma or a line break and be followed by the end of the input, a comma or a line break.

这篇关于逗号分隔数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！