从字符串中删除子字符串

Question

I have a string:

string valueA = "Free Chips (Save $43 / month)";

Now I want to retrieve string that occurs before (Save , ie I want Free Chips . How can I achieve this?

string valueB = valueA.Replace(); 

Answer 1

Use Substring and IndexOf

string valueB = valueA.Substring(0, valueA.IndexOf("(Save", StringComparison.Ordinal))
                      .Trim();

Answer 2

You can use a regex with positive lookahead :

.*?(?=\s*\(Save)

The full code:

using System.Text.RegularExpressions;

string query = "Free Chips (Save $43 / month)";

// ...

Regex r = new Regex(@".*?(?=\s*\(Save)");

Match m = r.Match(query);
if(m.Success) {
    string result = m.ToString(); // result = "Free Chips"
}

m.Success is false if "(Save" is not part of the string.

Answer 3

One of the ways is regex (of course for such a simple string it could be an little overhead):

var regex = new Regex("(.*)\(Save");
// (.*) - match anything and group it
// \(Save - match "(Save" literally
var regexMatch = regex.Match(valueA);
if (regexMatch.Success)
{
    var valueB = regex.Match(valueA).Groups[1].Value;
    //and so on
}

Answer 4

string valueA = "Free Chips (Save $43 / month)";
string valueB = valueA.Substring(0, valueA.IndexOf(" (Save"));