How to solve a usual problem in allocating the size of array

Question

I mean I want to ask user to enter the size of arrays when he/she uses my program instead of me, and when I use cin to get the size and put it as array size in brackets this error appear: the array size must have constant value and when I change the cin parameter as const int nothing happen, please guide me to solve this problem, Thank you.

Priyaranjan K S · Answer

Hi Joe You can try the below code to dynamically modify the array length during run time : int [] myArray = new int [ 5 ]{ 1  2  3  4  5 }; // Accept new array size from user int newArraySize = 10 ; for ( int i = 0 ; i newArraySize ; i ++ ) { Array . Resize ( ref myArray  newArraySize ); myArray [ myArray . Length - 1 ] = i ; } Console . WriteLine ( myArray . Length ); Output : 10 One important thing to note here is that the Array.Resize wont actually resize the array it will actually create a new array with the specified size and copies all the elements from the old array to the newly created array and then replaces the old array with the new array. Thanks Priyan If you found this useful Please mark this as Answer

Atul Rawat · Answer

use C# param arrays

Joe Wilson · Answer

I didn't exactly understand your answer please explain more I want end user to enter the size of arrays the program get run.

Joe Wilson · Answer

I exactly want to ask end user to enter the size of array then the program get runso COULD YOU EXPLAIN THE SOLUTION PLEASE?

Rajeev Ranjan · Answer

So you are trying to assign the size of array at run time?? if yes then assign any value before the run your programe and use a simple logic to assign user entered value ( something like swapping) that make your code easier and your problem gets resolved.

Preeti Agrawalla · Answer

Hello dear This problem might occur because an user is entering a string value and we can't use string value as an array size. so it will be better to use try catch block or to check whether entered value is integer or not and provide a message to end user that please enter numbers.