Fra form til form.

Definerer du selv MyParentForm?

Se evt. om du kan bruge noget kode fra:
http://activedeveloper.dk/brevkassen/default.asp?category=20&question=410

her er et virkende eksempel på hvordan man kan gøre det:

------form1-----------
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace WindowsApplication2
{
    /// <summary>
    /// Summary description for Form1.
    /// </summary>
    public class Form1 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Button button1;
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;
        private Form2 m_form2;

        public Form1()
        {
            //
            // Required for Windows Form Designer support
            //
            InitializeComponent();

            //
            // TODO: Add any constructor code after InitializeComponent call
            //
        }

        public string GetText
        {
            get
            {
                return textBox1.Text;
            }
        }

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        protected override void Dispose( bool disposing )
        {
            if( disposing )
            {
                if (components != null)
                {
                    components.Dispose();
                }
            }
            base.Dispose( disposing );
        }

        #region Windows Form Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.button1 = new System.Windows.Forms.Button();
            this.SuspendLayout();
            //
            // textBox1
            //
            this.textBox1.Location = new System.Drawing.Point(104, 104);
            this.textBox1.Name = "textBox1";
            this.textBox1.TabIndex = 0;
            this.textBox1.Text = "textBox1";
            //
            // button1
            //
            this.button1.Location = new System.Drawing.Point(112, 168);
            this.button1.Name = "button1";
            this.button1.TabIndex = 1;
            this.button1.Text = "button1";
            this.button1.Click += new System.EventHandler(this.button1_Click);
            //
            // Form1
            //
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(292, 266);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.textBox1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);

        }
        #endregion

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());
        }

        private void button1_Click(object sender, System.EventArgs e)
        {
            m_form2 = new Form2(this);
            m_form2.Show();
        }
    }
}
----------------form1 EOM--------------
----------------form2------------------
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;

namespace WindowsApplication2
{
    /// <summary>
    /// Summary description for Form2.
    /// </summary>
    public class Form2 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.Label label1;
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;

        public Form2()
        {
            //
            // Required for Windows Form Designer support
            //
            InitializeComponent();

            //
            // TODO: Add any constructor code after InitializeComponent call
            //
        }

        public Form2(Form1 Form1_)
        {
            //
            // Required for Windows Form Designer support
            //
            InitializeComponent();

            //
            // TODO: Add any constructor code after InitializeComponent call
            //
            label1.Text = Form1_.GetText;
        }

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        protected override void Dispose( bool disposing )
        {
            if( disposing )
            {
                if(components != null)
                {
                    components.Dispose();
                }
            }
            base.Dispose( disposing );
        }

        #region Windows Form Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.label1 = new System.Windows.Forms.Label();
            this.SuspendLayout();
            //
            // label1
            //
            this.label1.Location = new System.Drawing.Point(96, 96);
            this.label1.Name = "label1";
            this.label1.TabIndex = 0;
            this.label1.Text = "label1";
            //
            // Form2
            //
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(292, 266);
            this.Controls.Add(this.label1);
            this.Name = "Form2";
            this.Text = "Form2";
            this.ResumeLayout(false);

        }
        #endregion
    }
}
------------form2 EOM---------------

moonduck: Ja jeg har selv defineret MyParentForm:
public Form1 MyParentForm;
Jeg prøver at skrive sådan her i form2
label1.Text = Form1_.pris.ToString();
Fordi jeg vil have pris variablen fra Form1 til at skrives i Label1.text i form2
Men den siger hele tiden. Cannot pass 'Lotto.Form1.pris' as ref or out, because 'Lotto.Form1.pris' is a marshal-by-reference class

Jeg fandt selv ud af det... men ellers tak for hjælpen

ok. og hvad fandt du såå ud af..... ?!