Drag and drop TextBox control form toolbox on the window Form.

Add text in TextBox

private void frmTextBoLoad(object sender, EventArgs e)
        {
            textBox1.Text= "Hello";
        }

Hello text will show in the TextBox when application run.

TextBox as Input Control

Write the code on button click and assign the text box value in text properties of label

private void button1_Click(object sender, EventArgs e)
        {
            //TextBoxtext will show in label on button click
            label1.Text= textBox1.Text;
        }

When you entered Text in TextBox and click submit button then entered text will show in Label.

TextBox Properties

CharacterCasing:   set Character Case

•   Normal - The case of characters is left unchanged.
•   Lower - Converts all characters to lowercase.
•   Upper - Converts all characters to uppercase.

Multiline:  Indicates whether this is a multiline TextBox control.

PasswordChar:  Specifies the character used to mask characters of a password in a single-line TextBox control.

ScrollBars:  Specifies which scroll bars should appear in a multiline TextBox control.

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