Use Selection Expand (Ctrl + W) to select the code block in which the caret is located. You can use this command multiple times to increase the selected box's size. The Selection Reduce (Ctrl + Shift + W) is the opposite command: it undoes the Selection Expand and makes the selected block smaller.
You can also use the NumPad Plus to expand and NumPad Minus to reduce the selection box's size - enable these shortcuts on the IDE | Shortcuts options page in the Selection | Defining group.
To enable this feature, use the IDE or Shortcuts options page - open the Selection | Structure group and enable the two shortcuts in it.
Use Ctrl + Alt + Shift + Up Arrow or Ctrl + Alt + Shift + Down Arrow to select the text between the caret's current position and the end of the next code element.