親フォルダ
using System;
using System.Drawing;
using System.Windows.Forms;

namespace BuildField
{
	public partial class Form1 : Form
	{
		private TextBox[] textBoxArray;

		public Form1()
		{
			InitializeComponent();
			controlInit();
		}

		private void controlInit()
		{

			int fieldCount = 25;

			textBoxArray = new TextBox[fieldCount];

			for (int i = 0; i < fieldCount; i++)
			{

				this.textBoxArray[i] = new TextBox();
				this.textBoxArray[i].Location = new Point(144, 29 + i * 35);
				this.textBoxArray[i].Name = $"textBox{i}";
				this.textBoxArray[i].Size = new Size(588, 19);
				this.textBoxArray[i].TabIndex = i;
				this.Controls.Add(this.textBoxArray[i]);

			}

			Console.WriteLine($"フィールドを{fieldCount}個作成しました");
		}

	}
}