create list of structure and add to list

Question

I Write this code in c#  i declare array of structure but i do not know size of this array  I do not know how declare size for array of structure i know about list and i try use it  but i do not know how add to list (xbybsize)with structure and how declare it? public struct blocks { public Int32 xb; public Int32 yb; public Int32 size; }; namespace test { class Program { static static List blocks1 = new List (); static void Main ( string [] args) { Int32 index =0; for ( int y = 1 ; y 5 ; y++) for ( int x = 1 ; x 5 ; x++) { blocks1[index].xb=x * 2 ; // store start point (x) of block blocks1[index].yb = y * 2 ; // store start point (y) of block blocks1[index].size = 2 ; // store block size index++; } } } }

Vulpes · Answer

The easiest way to create an instance of a struct is to add a constructor which initializes all the fields of the struct at once. However if for some reason you don't want to add a constructor you can also use an 'object initializer' or just set the fields individually which you were already attempting to do in your post. An array of structs is created in the same way as any other array though the length needs to be known in advance. If you don't know the length then you can create a List of structs instead which increases its size dynamically as new elements are added. To add an element to the List the Add method should be used. Here are some examples of all this: using System; using System.Collections.Generic; public struct blocks { public Int32 xb; public Int32 yb; public Int32 size; public blocks(Int32 xb Int32 yb Int32 size) { this.xb = xb; this.yb = yb; this.size = size; } }; namespace test { class Program { static List blocks1 = new List (); static void Main() { // create array with 5 elements blocks[] blocks2 = new blocks[5]; // populate it using constuctor for(int x = 0; x { blocks2[x] = new blocks(x*2 x*2 2); } // create another array blocks[] blocks3 = new blocks[5]; // populate it using object initialize for(int x = 0; x { blocks3[x] = new blocks {xb = x*2 yb = x*2 size = 2}; } // create a third array blocks[] blocks4 = new blocks[5]; // populate it by setting individual fields // note that when you create an array of structs all fields are automatically // set to their default values which are 0 for numbers for(int x = 0; x { blocks4[x].xb = x * 2; blocks4[x].yb = x * 2; blocks4[x].size = 2; } // add elements to the list using constructor for(int x = 0; x { blocks1.Add(new blocks(x*2 x*2 2)); } //print some values Console.WriteLine(blocks1[0].xb); // 0 Console.WriteLine(blocks2[1].yb); // 2 Console.WriteLine(blocks3[2].size); // 2 Console.WriteLine(blocks4[3].xb); // 6 Console.ReadKey(); } } }