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iOS Objective-C Basics (Retired) Pointers and Memory Pointer Power


can anyone explain the use of %s in an objective c code.

When do you use it? Why do you use it?

Thank you

6 Answers

Its is the placeholder for example let say you are in a classroom you put your bags or books as placeholder which represent you Let try understand by code. <code> String name= "your name" printf(my name is %s",name); </code> The string variable will be substitute at the placeholder. Note:there is nothing like string type in C

%s is for a string of characters. Earlier in this course we've used %c for characters, %d for integers, %f for floats. Here we use %s for a string as we're pointing to several characters bound together in an array so %c wouldn't work anymore.

Can you be more specific? There is many ways you can use that, did you mean String Format Specifiers in general or just %s ?

not string format specifiers, just %s.

specifically in this piece of code

char sahil[ ] = "sahil"; letter = &sahil[2]; printf("%c is in %s\n",*letter, sahil);

Now, when I try to do that example of code you showed, it came out to be incorrect.

But when I put [ ] after String name [ ] = "your name" printf(my name is %s",name);

Then the code was performed well in Xcode.

What does relation does [ ] have with %s?

Thank you very much

That's is array string is a chunks of character bind together in array.using array we declare how much character we want Suppose you want store your name so you need 14 characters last one for /0