c# - 使用正则表达式将部分字符串转换为双精度

Question

我的应用程序似乎因“错误格式”而崩溃，我有这个：

Match m = Regex.Match(value, "[0-9]+[.[0-9]+]?");
double number = Convert.ToDouble(m.Value);
return number;

重点是使字符串值像这样：114.6W, 120.6W.变成我可以排序的值。我编写的函数假设将任何字符串转换为 9999.9999 双精度值，但它在Convert.ToDouble(). 输入格式错误？

score 2 · Accepted Answer

问题出在你的正则表达式上：它应该是

[0-9]+(\.[0-9]+)?

[.[0.9]+]（我对它的解析感到惊讶）是一个字符类，用于查找以下集合中的任何字符：点、开始和结束括号、0 到 9 或加号。

score 2 · Accepted Answer

也许这.不是您正在使用的文化的小数分隔符。InvariantCulture解析时尝试指定：

double number = Convert.ToDouble(m.Value, CultureInfo.InvariantCulture);

score 0 · Accepted Answer

Try these two regexes, you may need to test and adjust to your needs

this one will grab all numbers including the ., but only if followed by a W (won't grab the w)

(?i)\d+\.\d+(?=w)

this one will grab all the digits regardless what's after it

\d+\.\d+

or if your data sets consists of only the numbers plus one letter and nothing in front or after it, do as @paul suggests, just strip the last char

score 0 · Accepted Answer

0

您必须用括号替换方括号

Match m = Regex.Match(value, @"[0-9]+(?:\.[0-9]+)?");

于 2013-05-29T15:29:36.383 回答

score 0 · Accepted Answer

如果保证始终是十进制数字后跟单个字母，则：

var word = "120.6W";
var d = Decimal.Parse(word.Substring(0,word.Length-1));

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