Validate text box value : Validation « GUI Windows Forms

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;





   public class Form1 : Form

   {

      public Form1()

      {

         InitializeComponent();

         this.buttonOK.Enabled = false;

         this.textBoxAddress.Tag = false;

         this.textBoxAge.Tag = false;

         this.textBoxName.Tag = false;



         this.textBoxName.Validating += new CancelEventHandler(textBoxEmpty_Validating);

         this.textBoxAddress.Validating += new CancelEventHandler(textBoxEmpty_Validating);

         this.textBoxAge.Validating += new CancelEventHandler(textBoxEmpty_Validating);

      }



      void textBoxEmpty_Validating(object sender, CancelEventArgs e)

      {

         TextBox tb = (TextBox)sender;

         if (tb.Text.Length == 0)

         {

            tb.BackColor = Color.Red;

            tb.Tag = false;

         }

         else

         {

            tb.BackColor = System.Drawing.SystemColors.Window;

            tb.Tag = true;

         }

         ValidateOK();

      }



      private void buttonOK_Click(object sender, EventArgs e)

      {

         string output;

         output = this.textBoxName.Text + "\r\n";

         this.textBoxOutput.Text = output;

      }

      private void buttonHelp_Click(object sender, EventArgs e)

      {

         this.textBoxOutput.Text = "No";

      }



      private void textBoxAge_KeyPress(object sender, KeyPressEventArgs e)

      {

         if ((e.KeyChar < 48 || e.KeyChar > 57) && e.KeyChar != 8)

            e.Handled = true; 

      }



      private void textBox_TextChanged(object sender, EventArgs e)

      {

         TextBox tb = (TextBox)sender;

         if (tb.Text.Length == 0)

         {

            tb.Tag = false;

            tb.BackColor = Color.Red;

         }

         else

         {

            tb.Tag = true;

            tb.BackColor = SystemColors.Window;

         }

         ValidateOK();

      }



      private void ValidateOK()

      {

         this.buttonOK.Enabled = ((bool)(this.textBoxAddress.Tag) &&

                                 (bool)(this.textBoxAge.Tag) &&

                                 (bool)(this.textBoxName.Tag));

      }



      private void InitializeComponent()

      {

         this.labelName = new System.Windows.Forms.Label();

         this.textBoxName = new System.Windows.Forms.TextBox();

         this.buttonOK = new System.Windows.Forms.Button();

         this.textBoxAddress = new System.Windows.Forms.TextBox();

         this.labelAddress = new System.Windows.Forms.Label();

         this.buttonHelp = new System.Windows.Forms.Button();

         this.labelAge = new System.Windows.Forms.Label();

         this.textBoxAge = new System.Windows.Forms.TextBox();

         this.labelOutput = new System.Windows.Forms.Label();

         this.textBoxOutput = new System.Windows.Forms.TextBox();

         this.checkBoxProgrammer = new System.Windows.Forms.CheckBox();

         this.groupBox1 = new System.Windows.Forms.GroupBox();

         this.radioButtonMale = new System.Windows.Forms.RadioButton();

         this.radioButtonFemale = new System.Windows.Forms.RadioButton();

         this.groupBox1.SuspendLayout();

         this.SuspendLayout();

         // 

         // labelName

         // 

         this.labelName.AutoSize = true;

         this.labelName.Location = new System.Drawing.Point(12, 9);

         this.labelName.Name = "labelName";

         this.labelName.Size = new System.Drawing.Size(35, 13);

         this.labelName.TabIndex = 0;

         this.labelName.Text = "Name";

         // 

         // textBoxName

         // 

         this.textBoxName.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)

                     | System.Windows.Forms.AnchorStyles.Right)));

         this.textBoxName.Location = new System.Drawing.Point(98, 6);

         this.textBoxName.Name = "textBoxName";

         this.textBoxName.Size = new System.Drawing.Size(277, 20);

         this.textBoxName.TabIndex = 1;

         this.textBoxName.TextChanged += new System.EventHandler(this.textBox_TextChanged);

         // 

         // buttonOK

         // 

         this.buttonOK.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));

         this.buttonOK.Location = new System.Drawing.Point(381, 4);

         this.buttonOK.Name = "buttonOK";

         this.buttonOK.Size = new System.Drawing.Size(75, 23);

         this.buttonOK.TabIndex = 2;

         this.buttonOK.Text = "OK";

         this.buttonOK.UseVisualStyleBackColor = true;

         this.buttonOK.Click += new System.EventHandler(this.buttonOK_Click);

         // 

         // textBoxAddress

         // 

         this.textBoxAddress.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)

                     | System.Windows.Forms.AnchorStyles.Right)));

         this.textBoxAddress.Location = new System.Drawing.Point(98, 32);

         this.textBoxAddress.Multiline = true;

         this.textBoxAddress.Name = "textBoxAddress";

         this.textBoxAddress.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;

         this.textBoxAddress.Size = new System.Drawing.Size(277, 100);

         this.textBoxAddress.TabIndex = 3;

         this.textBoxAddress.TextChanged += new System.EventHandler(this.textBox_TextChanged);

         // 

         // labelAddress

         // 

         this.labelAddress.AutoSize = true;

         this.labelAddress.Location = new System.Drawing.Point(12, 35);

         this.labelAddress.Name = "labelAddress";

         this.labelAddress.Size = new System.Drawing.Size(45, 13);

         this.labelAddress.TabIndex = 4;

         this.labelAddress.Text = "Address";

         // 

         // buttonHelp

         // 

         this.buttonHelp.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));

         this.buttonHelp.CausesValidation = false;

         this.buttonHelp.Location = new System.Drawing.Point(381, 30);

         this.buttonHelp.Name = "buttonHelp";

         this.buttonHelp.Size = new System.Drawing.Size(75, 23);

         this.buttonHelp.TabIndex = 5;

         this.buttonHelp.Text = "Help";

         this.buttonHelp.UseVisualStyleBackColor = true;

         this.buttonHelp.Click += new System.EventHandler(this.buttonHelp_Click);

         // 

         // labelAge

         // 

         this.labelAge.AutoSize = true;

         this.labelAge.Location = new System.Drawing.Point(12, 255);

         this.labelAge.Name = "labelAge";

         this.labelAge.Size = new System.Drawing.Size(26, 13);

         this.labelAge.TabIndex = 8;

         this.labelAge.Text = "Age";

         // 

         // textBoxAge

         // 

         this.textBoxAge.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)

                     | System.Windows.Forms.AnchorStyles.Right)));

         this.textBoxAge.Location = new System.Drawing.Point(98, 252);

         this.textBoxAge.MaxLength = 3;

         this.textBoxAge.Name = "textBoxAge";

         this.textBoxAge.Size = new System.Drawing.Size(277, 20);

         this.textBoxAge.TabIndex = 9;

         this.textBoxAge.TextChanged += new System.EventHandler(this.textBox_TextChanged);

         this.textBoxAge.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.textBoxAge_KeyPress);

         // 

         // labelOutput

         // 

         this.labelOutput.AutoSize = true;

         this.labelOutput.Location = new System.Drawing.Point(12, 271);

         this.labelOutput.Name = "labelOutput";

         this.labelOutput.Size = new System.Drawing.Size(39, 13);

         this.labelOutput.TabIndex = 10;

         this.labelOutput.Text = "Output";

         // 

         // textBoxOutput

         // 

         this.textBoxOutput.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)

                     | System.Windows.Forms.AnchorStyles.Left)

                     | System.Windows.Forms.AnchorStyles.Right)));

         this.textBoxOutput.Location = new System.Drawing.Point(15, 287);

         this.textBoxOutput.Multiline = true;

         this.textBoxOutput.Name = "textBoxOutput";

         this.textBoxOutput.ReadOnly = true;

         this.textBoxOutput.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;

         this.textBoxOutput.Size = new System.Drawing.Size(360, 168);

         this.textBoxOutput.TabIndex = 11;

         // 

         // checkBoxProgrammer

         // 

         this.checkBoxProgrammer.AutoSize = true;

         this.checkBoxProgrammer.Checked = true;

         this.checkBoxProgrammer.CheckState = System.Windows.Forms.CheckState.Checked;

         this.checkBoxProgrammer.Location = new System.Drawing.Point(15, 138);

         this.checkBoxProgrammer.Name = "checkBoxProgrammer";

         this.checkBoxProgrammer.Size = new System.Drawing.Size(88, 17);

         this.checkBoxProgrammer.TabIndex = 12;

         this.checkBoxProgrammer.Text = "Programmer?";

         this.checkBoxProgrammer.UseVisualStyleBackColor = true;

         // 

         // groupBox1

         // 

         this.groupBox1.Controls.Add(this.radioButtonMale);

         this.groupBox1.Controls.Add(this.radioButtonFemale);

         this.groupBox1.Location = new System.Drawing.Point(15, 161);

         this.groupBox1.Name = "groupBox1";

         this.groupBox1.Size = new System.Drawing.Size(360, 85);

         this.groupBox1.TabIndex = 13;

         this.groupBox1.TabStop = false;

         this.groupBox1.Text = "Sex";

         // 

         // radioButtonMale

         // 

         this.radioButtonMale.AutoSize = true;

         this.radioButtonMale.Checked = true;

         this.radioButtonMale.Location = new System.Drawing.Point(187, 33);

         this.radioButtonMale.Name = "radioButtonMale";

         this.radioButtonMale.Size = new System.Drawing.Size(48, 17);

         this.radioButtonMale.TabIndex = 1;

         this.radioButtonMale.TabStop = true;

         this.radioButtonMale.Text = "Male";

         this.radioButtonMale.UseVisualStyleBackColor = true;

         // 

         // radioButtonFemale

         // 

         this.radioButtonFemale.AutoSize = true;

         this.radioButtonFemale.Location = new System.Drawing.Point(58, 33);

         this.radioButtonFemale.Name = "radioButtonFemale";

         this.radioButtonFemale.Size = new System.Drawing.Size(59, 17);

         this.radioButtonFemale.TabIndex = 0;

         this.radioButtonFemale.Text = "Female";

         this.radioButtonFemale.UseVisualStyleBackColor = true;

         // 

         // Form1

         // 

         this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);

         this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;

         this.ClientSize = new System.Drawing.Size(468, 466);

         this.Controls.Add(this.groupBox1);

         this.Controls.Add(this.checkBoxProgrammer);

         this.Controls.Add(this.textBoxOutput);

         this.Controls.Add(this.labelOutput);

         this.Controls.Add(this.textBoxAge);

         this.Controls.Add(this.labelAge);

         this.Controls.Add(this.buttonHelp);

         this.Controls.Add(this.labelAddress);

         this.Controls.Add(this.textBoxAddress);

         this.Controls.Add(this.buttonOK);

         this.Controls.Add(this.textBoxName);

         this.Controls.Add(this.labelName);

         this.MinimumSize = new System.Drawing.Size(484, 370);

         this.Name = "Form1";

         this.Text = "Form1";

         this.groupBox1.ResumeLayout(false);

         this.groupBox1.PerformLayout();

         this.ResumeLayout(false);

         this.PerformLayout();

      }

      private System.Windows.Forms.Label labelName;

      private System.Windows.Forms.TextBox textBoxName;

      private System.Windows.Forms.Button buttonOK;

      private System.Windows.Forms.TextBox textBoxAddress;

      private System.Windows.Forms.Label labelAddress;

      private System.Windows.Forms.Button buttonHelp;

      private System.Windows.Forms.Label labelAge;

      private System.Windows.Forms.TextBox textBoxAge;

      private System.Windows.Forms.Label labelOutput;

      private System.Windows.Forms.TextBox textBoxOutput;

      private System.Windows.Forms.CheckBox checkBoxProgrammer;

      private System.Windows.Forms.GroupBox groupBox1;

      private System.Windows.Forms.RadioButton radioButtonFemale;

      private System.Windows.Forms.RadioButton radioButtonMale;



      [STAThread]

      static void Main()

      {

         Application.EnableVisualStyles();

         Application.SetCompatibleTextRenderingDefault(false);

         Application.Run(new Form1());

      }

   }
Validate text box value : Validation « GUI Windows Forms « C# / CSharp Tutorial
