This is a pretty basic question, but here it goes: Is there a string method in C# that adds a number of characters from a string to another string? In C++ std::string class, there was the append method that had three parameters: source string, indexStart, offset.
string a = "foo";
string b = "bar";
a.append(b, 0, 2); // a is now "fooba";
In C# I also tried with StringBuilder, but no luck.
Strings in .NET are immutable. Once a string is created, you can't modify it. However, you can create a new string by concatenation, and reassign it to the same variable:
string a = "foo";
string b = "bar";
a = a + b.Substring(0, 2); // a is now "fooba";
string a = "foo";
string b = "bar";
var sb = new StringBuilder();
sb.append(a);
sb.append(b.SubString(0,2));
string res = sb.ToString(); // res = "fooba"
If you're feeling adventurous, you could also write an extension method:
public static class MyStringExtensions
{
public static string Append(this string original, string textToAdd, int length)
{
if (length <= 0)
{
return original;
}
var len = (textToAdd.Length < length)
? textToAdd.Length
: length;
return original + textToAdd.Substring(0, len);
}
}
Then to use it you would go like this:
string a = "foo".Append("bar", 2);
or
string a = "foo";
string b = "bar";
string c = a.Append(b, 2);
This also has the nice advantage of allowing error/exception handling in a central location.
Try doing
string aa = "foo";
string bb = "bad";
bb= string.Concat(aa, bb.Substring(0, 2));
