What are the blocks? How will you use them?

1.	What are the blocks? How will you use them?
Answer» Blocks are language-level features that are added to Objective C, C, and C++. Blocks ALLOW you to create SEGMENTS of code that can be passed to methods or functions as values. SYNTAX to define a BLOCK uses the caret symbol (^): ^{ NSLog(@”This is a block”); } 19. What is a responder chain? Responder chain is a series of responder objects that are linked together. A chain starts with the first responder and ENDS with the app object. However, when the first responder is unable to handle an event, it forwards it to the next responder in the chain.

Answer»

Blocks are language-level features that are added to Objective C, C, and C++. Blocks ALLOW you to create SEGMENTS of code that can be passed to methods or functions as values. SYNTAX to define a BLOCK uses the caret symbol (^):
^{
NSLog(@”This is a block”);
}

19. What is a responder chain?

Responder chain is a series of responder objects that are linked together. A chain starts with the first responder and ENDS with the app object. However, when the first responder is unable to handle an event, it forwards it to the next responder in the chain.

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