Why do I get a StringFormat error with this?

Question

With this code (sbJava is a StringBuilder):

String androidFindLine = string.Format("Button _{0} = (Button) findViewById(R.id.{0});\"", btnId);
sbJava.Append(androidFindLine);
sbJava.Append(Environment.NewLine);
sbJava.Append(string.Format("_{0}.setOnClickListener(new View.OnClickListener() { ", btnId));

...I get,

System.FormatException was unhandled _HResult=-2146233033 _message=Input string was not in a correct format...

The value of btnId is "btnbutton_up"

What is the problem?

Answer 1

You should escape those { with double {{:

sbJava.Append(string.Format("_{0}.setOnClickListener(new View.OnClickListener() {{ ", btnId));