I am trying to initialize 2-dimensional array of integer values with -1. When I create a new array, it is automatically filled with 0. I know I can do it with 2 for cycles, but I imagine there should be some way of doing this while the array is being build (so I don't have to go through it two times), so that instead of 0, provided value would be inserted. Is it possible? If not during the initial building of the array, is there some other time or code saving way, or am I stuck with 2 for cycles?
With a multidimensional array, the loops are most likely the best approach, unless the array is small enough to initialize directly in code.
If you're using a jagged array, you could initialize the first sub-array, then use Array.Copy to copy these values into each other sub-array. This will still require one iteration through the first sub array, and one loop through N-1 outer arrays, but the copy operation will be faster than the loops.
Try something like this: int[,] array2D = new int[,] { { -1 }, { -1 }, { -1 }, { -1} };
or with dimension int[,] array2D = new int[4,2] { { -1,-1 }, { -1,-1 }, { -1,-1 }, {-1,-1} };
来源：https://stackoverflow.com/questions/15079215/how-to-initialize-multi-dimensional-array-with-different-default-value