How to check if an array is empty or empty?

Question

I want to check if my array or zero is empty, and based on which I want to create a condition, for example.

if(array == EMPTY){ //do something } 

Hope I understand what I'm asking, just need to check if my array is empty?

considers

Answer 1

 if (!array || !array.count){ ... } 

This checks if the array is nil, and if not, check if it is empty.

Answer 2

 if ([array count] == 0) 

If the array is nil, it will also be 0, since nil displays 0; therefore, checking whether an array exists is not required.

In addition, you should not use array.count as suggested. This may work, but it is not a property, and will list everyone who reads your code nuts if they know the difference between the property and the method.

UPDATE: Yes, I know that years later the account is now officially owned.

Answer 3

you can try like this

 if ([array count] == 0) 

Answer 4

Just to be really verbose :)

 if (array == nil || array.count == 0) 

Answer 5

The best performance.

 if (array.firstObject == nil) { // The array is empty } 

The way to work with large arrays.

Answer 6

 if (array == (id)[NSNull null] || [array count] == 0) { NSLog(@"array is empty"); } 

Answer 7

Since nil displays 0, which is NO , the most elegant way should be

 if (![array count]) 

The operator '==' is not needed.

Answer 8

You can also perform such a test using if (nrow> 0). If your data object is not formally an array, it might work better.

Answer 9

null and empty are not the same, I suggest you treat them differently

 if (array == [NSNull null]) { NSLog(@"It null"); } else if (array == nil || [array count] == 0) { NSLog(@"It empty"); } 

Answer 10

Swift 3

As in the latest version of swift 3, the option to compare s> and <options is not available

You can still compare options with the == symbol, so the best way to check if the extra array contains values ​​is:

 if array?.isEmpty == false { print("There are objects!") } 

by the number of arrays

 if array?.count ?? 0 > 0 { print("There are objects!") } 

There are other ways and can be checked here link to answer

Answer 11

 if (array == nil || array.count == 0 || [array isEqaul [NSNull Null]]) 

Answer 12

In Swift 4

 if (array.isEmpty) { print("Array is empty") } else{ print("Array is not empty") }