Textbox and RichTextbox are look like same.But don't know the difference.Please tell me anyone, When i have to use TextBox and RichTextbox as well in wpf.
See this Microsoft overview of the differences between a TextBox and a RichTextBox.
From above Link:
Both RichTextBox and TextBox allow users to edit text, however, the two controls are used in different scenarios. A RichTextBox is a better choice when it is necessary for the user to edit formatted text, images, tables, or other rich content. For example, editing a document, article, or blog that requires formatting, images, etc is best accomplished using a RichTextBox. A TextBox requires less system resources then a RichTextBox and it is ideal when only plain text needs to be edited (i.e. usage in forms).