java - 什么正则表达式将在收据上列出最后的价格？

Question

我有以下表达式:

(?!\d+\s+TOTAL\s+)\$+\d+\.?\d+\s+

它根据以下文本生成结果“$23.00$0.03$23.80”:

SPEEDWAY 3007906          
Wallace NC 28466          
TRAM: 1086244             
9/17/2017  2:12 pm        
Pump 08                   
Regular Unleaded          
8,716 @ $2,639/6131       
GAS TOTAL           $23.00
TAX                 $0.03 
TOTAL               $23.80
Uisa                     

在这种情况下，什么正则表达式只会提取 $23.80 ？如果我添加正向前瞻，则表达式为 "(?!\d+\s+TOTAL\s+)\$+\d+\.?\d+\s+(?=.*\$\d+\. ?\d+)”，结果是“$23.00$0.03”而不是“$23.80”。请帮忙。提前致谢。

Answer 1

试试这个:

(?<=^TOTAL)\s*(\$\s*\d+\.?\d*)\s*$

确保您使用MULTILINE匹配。

这将匹配值周围的所有空格，因此您可能需要删除这些空格来获取值

示例:

String in = "SPEEDWAY 3007906\n" +          
"Wallace NC 28466          \n" +
"TRAM: 1086244             \n" +
"9/17/2017  2:12 pm        \n" +
"Pump 08                   \n" +
"Regular Unleaded          \n" +
"8,716 @ $2,639/6131       \n" +
"GAS TOTAL           $23.00\n" +
"TAX                 $0.03 \n" +
"TOTAL               $23.80\n" +
"Uisa          ";

Pattern p = Pattern.compile("(?<=^TOTAL)\\s*(\\$\\s*\\d+\\.?\\d*)\\s*$", MULTILINE);
Matcher m = p.matcher(in);

if(m.find()) {
    System.out.println(m.group(1));
}

这应该只打印匹配的值