C#:如何有效地从预定义的字符串格式中提取值?

一个正则表达式就可以了。

namespace ConsoleApplication
{
    using System;
    using System.Text.RegularExpressions;

    internal static class Program
    {
        private static void Main()
        {
            var expression = new Regex(
                @"Customer's first Name is (?<FirstName>[^,]+), " +
                @"his last name is (?<LastName>[^,]+), " +
                @"his company name is (?<CompanyName>[^,]+), " +
                @"he has a balance of (?<Balance>[0-9]+) dollars\. " +
                @"His spending rate is (?<SpendingRate>[^%]+)%");

            var line = @"Customer's first Name is john, his last name is glueck, his company name is abc def technolgies llc, he has a balance of 60 dollars. His spending rate is +3.45%";

            var match = expression.Match(line);

            Console.WriteLine("First name......{0}", match.Groups["FirstName"]);
            Console.WriteLine("Last name.......{0}", match.Groups["LastName"]);
            Console.WriteLine("Balance.........{0}", match.Groups["Balance"]);
            Console.WriteLine("Spending rate...{0}", match.Groups["SpendingRate"]);

            Console.ReadLine();
        }
    }
}

First name......john
Last name.......glueck
Balance.........60
Spending rate...+3.45

之后,您可以执行一些简单的字符串解析,从字符串中获取数值。此外,如果输入的格式有一些变化,您可能需要编写一个更健壮的正则表达式。

(问题:您实际输入的字符串是完整的文字:“客户的名字是xxxx,他的姓是xxxx,他的公司名是xxxx”等等。正确吗?)

更新:

  // NOTE: pattern assumes a comma after spending rate
  Regex regex = new Regex("Customer's first Name is (\w+), his last name is (\w+),his company name is ([\w\s]+), he has a balance of (\d+) dollars.His spending rate is ([^,]+)");

  string[] values = regex.Split(string1);