我需要找到并提取字符串中包含的数字。
例如,从这些字符串:
string test = "1 test"
string test1 = " 1 test"
string test2 = "test 99"
我该怎么做呢?
我需要找到并提取字符串中包含的数字。
例如,从这些字符串:
string test = "1 test"
string test1 = " 1 test"
string test2 = "test 99"
我该怎么做呢?
当前回答
使用正则表达式…
Regex re = new Regex(@"\d+");
Match m = re.Match("test 66");
if (m.Success)
{
Console.WriteLine(string.Format("RegEx found " + m.Value + " at position " + m.Index.ToString()));
}
else
{
Console.WriteLine("You didn't enter a string containing a number!");
}
其他回答
static string GetdigitFromString(string str)
{
char[] refArray = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
char[] inputArray = str.ToCharArray();
string ext = string.Empty;
foreach (char item in inputArray)
{
if (refArray.Contains(item))
{
ext += item.ToString();
}
}
return ext;
}
下面是Linq版本:
string s = "123iuow45ss";
var getNumbers = (from t in s
where char.IsDigit(t)
select t).ToArray();
Console.WriteLine(new string(getNumbers));
下面是另一种Linq方法,它从字符串中提取第一个数字。
string input = "123 foo 456";
int result = 0;
bool success = int.TryParse(new string(input
.SkipWhile(x => !char.IsDigit(x))
.TakeWhile(x => char.IsDigit(x))
.ToArray()), out result);
例子:
string input = "123 foo 456"; // 123
string input = "foo 456"; // 456
string input = "123 foo"; // 123
有一个问题的答案正好相反: 如何使用Regex.Replace从字符串中删除数字?
// Pull out only the numbers from the string using LINQ
var numbersFromString = new String(input.Where(x => x >= '0' && x <= '9').ToArray());
var numericVal = Int32.Parse(numbersFromString);
正则表达式。Split可以从字符串中提取数字。你会得到在字符串中找到的所有数字。
string input = "There are 4 numbers in this string: 40, 30, and 10.";
// Split on one or more non-digit characters.
string[] numbers = Regex.Split(input, @"\D+");
foreach (string value in numbers)
{
if (!string.IsNullOrEmpty(value))
{
int i = int.Parse(value);
Console.WriteLine("Number: {0}", i);
}
}
输出:
数量:4 数量:40 数量:30 数量:10