Watch expressions allow you to monitor the values of variables, properties, and expressions at run time. Many debugging problems aren't immediately traceable to a single statement, so you may need to use a watch expression to observe the behavior of a variable or expression throughout a procedure.
The development environment automatically monitors the watch expressions you define. When the application enters break mode, these watch expressions appear in the Watch window, where you can observe their values.
To add a watch expression at design time or in break mode
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