一元表达式的无效参数类型'void'

Question

I'm writing iOS app and I've got this error:

Invalid argument type 'void' to unary expression

Here's the code:

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
  //code here
}

Answer 1

You got your method inside another method's body (maybe you've missed to type its closing } ?). That's why you get the error. Try to move it outside somewhere in your .m file.

Answer 2

Check the lines above your function. Do you have unbalanced parantheses? Did you declare some incomplete statement?