Passing subarrays as parameter

Question

Dear community How do I pass a subarray from a multidimensional array as a parameter to a function? In c the code would be like: int array[5][5]; array[3][1]= 3; dosomething(array[3]); // passes the 4th subarray to the function Declared as: void dosomething(int[]); How will the port to c# look like? int[][] array= new array[5][5]; // syntax error int[][] array= new array[55]; // compile error: cannot cast [] implicitely to [][] int[] array= new array[55]; array[3][1]= 3; dosomething(array[3]); // compile error 2 dimensions expected Can someone help me out? Thanks Carl

Alan · Answer

One thing I should perhaps have mentioned in my previous reply is that you can also declare multidimensional arrays in C#. These differ from 'jagged' arrays in that the array elements do have of be of the same length and they are therefore more akin to multidimensional arrays in C which also have to be rectangular. Confusingly though the syntax is different. Worse still there is (AFAIK) no easy way to obtain a subarray - you have to build them up manually. Anyway the previous code using a multidimensional array would look like this: int[] array = new int[55]; // all values set to zero array[31] = 3; int[] array3 = new int[5]; // declare one dimensional array to get subarray in 4th row for(int i = 0; i array3[i] = array[3 i]; dosomething(array3);

Alan · Answer

Because the array elements in a 'jagged' array don't necessarily have to be the same length you have to do something like this: int[][] array= new int[5][]; for (int i = 0; i array[i] = new int[5]; array[3][1]= 3; dosomething(array[3]);