如何将文本框值添加到数组并仅显示填充的数组位置？

Question

I have a array, its size is 100. So it is like this:

string[] Brands = new string[100];

I also have a TextBox on my Form . Everytime I click the Button , I want the TextBox to store its data in the array. After that I want the array to display the values into a ListBox . But, I only want the ListBox to display the actual used memory of the array. So I have 100 places in the array, but I only want to show the used ones.

Can someone please help me?

Answer 1

    int ArrayPos = 0;
    string[] Brands = new string[100];

            private void Button_Click(object sender, RoutedEventArgs e)
            {

             if(arrayPos < 100)
             {
             Brands[ArrayPos] = textBox.Text;
             listbox.add(Brands[ArrayPos]);
             ArrayPos++;

             }


            };

This will allow you to add items to the array at the next position as well as checking that the array is not full. Also It will then add the contents of the newly filled array position into the listbox.

Answer 2

What you're trying to do will be much easier if you use a List<string> instead.

List<string> Brands = new List<string>();

When you click the button, you can add your element to the list like this:

Brands.Add(textBox1.Text);

And when you want to show the number of elements (I assume that's what you mean by "actual used memory"), it's as easy as referencing the Count property:

int totalBrands = Brands.Count;

If for some reason you have a constraint that forces you to use a string[100] , this won't work.

Answer 3

According to the restriction, given that you can only use array, what you would probably need is something like this

int index = 0; //to tell the current position of the array "pointer"
string[] Brands = new string[100];

//And on your Button click event
private void button1_Click(object sender, EventArgs e) {
    if (index < Brands.Length) {
        Brands[index] = textBox1.Text;
        listBox1.Items.Add(Brands[index++]);                
    }
}

This way you add whatever is in the textBox1 at the event button1 is clicked to the position in the array which is pointed by your index value. And as long as your index is not greater than the Brands.Length you can always add item to your listBox1 by using listBox1.Items.Add .