在Form构造函数中更改TextBox Text属性不会影响绑定设置

Question

为什么当我更改Form构造函数中的TextBox Text属性时，它不会影响绑定设置？

样品： 表单中的TextBox。 Text属性绑定到Settings字符串。 如果在Form构造函数中更改了TextBox.Text，则绑定的Setting不会更改其值。虽然在构造之外，它确实发生了变化（如预期的那样，因为它们是绑定的）。

我不知道绑定＆＃34;魔法＆＃34;工作，也许我在这里遗漏了一些东西。但这种行为至少是奇怪的。

代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using WindowsFormsApplication1.Properties;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            ChangeText();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            ChangeText();
        }

        private void ChangeText()
        {
            //Settings.Default.TextBox1Text == "Original settings value"
            textBox1.Text = "Changed";

            //Call to this method inside Constructor:
            // Settings.Default.TextBox1Text still equals its original value
            //Settings.Default.TextBox1Text == "Original settings value"

            //Call to this method outside Constructor:
            // Settings.Default.TextBox1Text == "Changed"
        }
    }
}

namespace WindowsFormsApplication1
{
    partial class Form1
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (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.DataBindings.Add(new System.Windows.Forms.Binding("Text", global::WindowsFormsApplication1.Properties.Settings.Default, "TextBox1Text", true, System.Windows.Forms.DataSourceUpdateMode.OnPropertyChanged));
            this.textBox1.Location = new System.Drawing.Point(12, 41);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(100, 20);
            this.textBox1.TabIndex = 0;
            this.textBox1.Text = global::WindowsFormsApplication1.Properties.Settings.Default.TextBox1Text;
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(157, 41);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(75, 23);
            this.button1.TabIndex = 1;
            this.button1.Text = "button1";
            this.button1.UseVisualStyleBackColor = true;
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(284, 262);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.textBox1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Button button1;
    }
}