using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace TextBox_1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            textBox1.PasswordChar = '@'; //設(shè)置文本框的PasswordChar屬性為字符@
            textBox2.UseSystemPasswordChar = true;
            //設(shè)置文本框的UseSystemPasswordChar屬性為True;
        }

        private void label1_Click(object sender, EventArgs e)
        {

        }
    }
}
    

program.cs:

      using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;

namespace TextBox_1
{
    static class Program
    {
        /// <summary>
        /// 應(yīng)用程序的主入口點。
        /// </summary>
        [STAThread]
        static void Main()
        {
            //Enabled 獲取或設(shè)置一個值,該值指示控件能否夠?qū)τ脩艚换プ龀鲰憫?yīng)
            //ForeColor:獲取或設(shè)置控件的前景色
            //Modifiers:指示TextBox控件的可見性級別
            //Multiline://獲取或設(shè)置字符,該字符用于
            //PasswordChar:獲取或設(shè)置字符
            //                          :public char PasswordChar{get; set;}
            //ReadOnly:獲取或設(shè)置一個值,該值指示文本框中的文本是否為僅僅讀
            //               :public bool ReadOnly{get ; set; }
            //               :TextBox.ReadOnly=true;  將文本設(shè)置為僅僅讀
            //RightToLeft:獲取或設(shè)置一個值.該值指示是否將控件的元素對齊以支持使用從右向左的字體區(qū)域設(shè)置
            //ScrollBars:獲取或設(shè)置哪些滾動欄應(yīng)出如今多行TextBox控件中
            //Text:獲取或設(shè)置TextBox控件的文本
            //UseSystemPasswordChar:獲取或設(shè)置一個值,該值指示TextBox控件中的文本是否應(yīng)該以默認的password字符顯示
            //                                              :public Bool UseSystemPasswordChar{get ;set ;}
            //Visible:獲取或設(shè)置一個值,該值指示是否顯示該控件及其全部父控件
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());

        }
    }
}

    

Form設(shè)計:

      namespace TextBox_1
{
    partial class Form1
    {
        /// <summary>
        /// 必需的設(shè)計器變量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// 清理全部正在使用的資源。
        /// </summary>
        /// <param name="disposing">假設(shè)應(yīng)釋放托管資源，為 true。否則為 false。
      

      
      

        </param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows 窗口設(shè)計器生成的代碼

        /// <summary>
        /// 設(shè)計器支持所需的方法 - 不要
        /// 使用代碼編輯器改動此方法的內(nèi)容。
        /// </summary>
        private void InitializeComponent()
        {
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.label1 = new System.Windows.Forms.Label();
            this.label2 = new System.Windows.Forms.Label();
            this.SuspendLayout();
            // 
            // textBox1
            // 
            this.textBox1.Location = new System.Drawing.Point(155, 27);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(121, 21);
            this.textBox1.TabIndex = 0;
            // 
            // textBox2
            // 
            this.textBox2.Location = new System.Drawing.Point(155, 77);
            this.textBox2.Name = "textBox2";
            this.textBox2.Size = new System.Drawing.Size(121, 21);
            this.textBox2.TabIndex = 1;
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(66, 30);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(83, 12);
            this.label1.TabIndex = 2;
            this.label1.Text = "PassWordChar:";
            this.label1.Click += new System.EventHandler(this.label1_Click);
            // 
            // label2
            // 
            this.label2.AutoSize = true;
            this.label2.Location = new System.Drawing.Point(12, 80);
            this.label2.Name = "label2";
            this.label2.Size = new System.Drawing.Size(137, 12);
            this.label2.TabIndex = 3;
            this.label2.Text = "UseSystemPassWordChar:";
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(318, 151);
            this.Controls.Add(this.label2);
            this.Controls.Add(this.label1);
            this.Controls.Add(this.textBox2);
            this.Controls.Add(this.textBox1);
            this.Name = "Form1";
            this.Text = "登錄";
            this.Load += new System.EventHandler(this.Form1_Load);
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.Label label2;
    }
}