Substring Examples

Substring can be used two ways. The first is simply to create a new string from the characters starting at the startIndex to the end of the sting. The other version creates a new string at the startIndex followed by as many chracters as specified by the rangeIndex.

The general syntax for this method is:

//Option 1
stringName.Substring(startIndex);

//Option 2
stringName.Substring(startIndex, rangeIndex);

Both Option 1 and 2 return a new substring of stringName.

Example

//Option 1
Console.WriteLine("LaunchCode".Substring(4));

//Option 2
Console.WriteLine("LaunchCode".Substring(4, 3));

Output

//Option 1
chCode

//Option 2
chC

On some websites, the portion of an email address before the @ symbol is used as a username. We can extract this portion of an email address using Substring in conjunction with IndexOf.

Example

string input = "[email protected]";
int atIndex = input.IndexOf("@");
string username = input.Substring(0, atIndex);
Console.WriteLine(username);

Output

fake.email