Simple Insertion sort method

[AhmedGY]

Hi, am trying to build an app that uses the insertion sort method to sort numbers entered in a textbox and display them sorted in a label, so i wrote this inside the sort button click event:

label1.Text = Insertion.insert(textBox1.Text);

and here is the insertion class:

class Insertion
    {
        public static string insert(string x)
        {
            
            for (int i = 2; i < x.Length; ++i)
            {
                for (int j = i-1; j > 0 && x[j] < x[i]; --j)
                {
                    x[j] = x[i];
                }
            }
            return x.ToString();
        }
    }

Although it looks logical to me, it doesn't work and gives an error: Property or indexer 'string.this[int]' cannot be assigned to -- it is read only.

How to get this workin?

[AhmedGY]

Any help?

I tried to use int instead of string, however i don't know how to put string elements inside an array of integers.

Did it this way:

int[] str = new int[100]; 

            for (int k = 0; k < textBox1.Text.Length; k++)
            {
                string z=textBox1.Text;

                str[k] = textBox1.Text.IndexOf(z,k);  //this should put str[0]=textbox1.text[0] .. and so on
            }

but it doesn't work.