You can select one or more objects under the prompt of Select entities on the command line. The selected highlights on the screen and could be removed from the selection set.
Select objects with pickbox
You can select objects using mouse or other pointing device. The mouse or other pointing device is represented of square pickbox on the drawing area. When selecting object, the cursor square pickbox should be in the position of an object but not inside it. The size of pickbox can be changed on the Selection tab of Options dialog box.
Remove Selection from Objects
If an entity is no longer needed in a selection set, you can deselect it to remove it from the selection set.
To remove an entity from the selection set
Press Shift, and then select the entity again.
NOTE Pressing Shift while selecting entities using a crossing window removes all entities from the specified selection set.
To remove all entities from the selection set
Prevent Objects from Being Selected
You can prevent objects from being selected by locking layer. Because locking layer means that you can do any operations except for editing objects on this layer. You can set the locked layer as the current layer and add objects as well as using requiring command (such as LIST) and Objects Snap.
You can control whether you select objects first or type a command first, whether the selected objects is highlighted, how to define the selection area, how to create a selection set.
Select Objects First
You can select objects first and then choose how to modify them. As you select each object, it is highlighted with small squares called grips, which appear at strategic points on the object.
The locations of the grips depend on the type of object selected. For example, grips appear at the endpoints and midpoint of a line, at the quadrant points and center point of a circle, and at the endpoints, midpoint, and center of an arc.
Examples of grip locations.
After you select one or more objects, you can choose an object modification command, such as Copy or Move, from the Modify menu or toolbar. You can also click the right mouse button to display a shortcut menu containing the object modification commands appropriate for the selected objects, and then choose the command from the menu.
Select a Command First
After typing a command, the cursor becomes a pickbox and prompts you to select objects. There are several methods for selecting objects:
Select objects using mouse or other pointing device.
Click on the drawing area and drags the cursor to define a square selection area.
Entering interrogation ? displays all selection methods, from which, you can specify the desired one.
Use multiple methods together. For example, to select most of objects on the drawing, you can select all objects and then remove the undesired ones.
When you choose an entity-modification tool or command, the program prompts you to select entities. Type ? and press ENTER, you can choose a selection method. You can select individual entities or use other techniques such as selection windows to select multiple entities.
When you select objects, you add them to the selection set. After you select at least one object, you can remove objects from the selection set. To finish adding objects to the selection set, press Enter. Most object-modification commands then act on the entire selection set.
Control the highlight of selected objects
You can specify whether to display selected entities highlighted, which makes the selection set easier to see. By default, the highlighting feature is turned on.
Setting system variable HIGHLIGHT to 0 turns off the highlighting feature, which can improve the computer's performance. The operation does not affect grips.
Objects selection methods
When you choose a command that requires you to select entities (when you're deleting or changing entity properties, for example), you can use any of the following selection methods by choosing them in the command line prompt or entering them in the command bar:
Select all entities (ALL) Selects all entities in the current drawing.
Add to set (A) Adds one or more entities to the selection set.
Remove from set (R) Removes one or more entities from the selection set.
Previous selection (P) Selects entities included in the previous selection set.
Last entity in drawing (L) Selects the entity most recently added to the drawing.
Window (W) Selects entities contained entirely within a rectangular selection window.
Crossing window (C) Selects entities contained within or crossing the boundary of a rectangular selection window.
Outside window (O) Selects entities falling completely outside a rectangular selection window.
Window polygon (WP) Selects entities contained entirely within a polygon selection window.
Crossing polygon (CP) Selects entities contained within or crossing the boundary of a polygon selection window.
Outside polygon (OP) Selects entities falling completely outside a polygon selection window.
Window circle (WC) Selects entities contained entirely within a circular selection window.
Crossing circle (CC) Selects entities contained within or crossing the boundary of a circular selection window.
Outside circle (OC) Selects entities falling completely outside a circular selection window.
Box (B) Selects all entities completely inside a box.
Point (PO) Selects any closed entities that surround the selected point.
Fence (F) Selects all entities crossing a selection box.
Select by Properties (PRO) Selects all entities by properties.
PROPERTIES: Controls properties of existing objects
QSELECT: Creates a selection set based on filtering criteria
SELECT: Groups entities into a selection set for use in subsequent commands
LAYER: Manages layers and layer properties
System Variables Reference
HIGHLIGHT: Controls object highlighting; does not affect objects selected with grips
PICKADD: Controls whether subsequent selections replace the current selection set or add to it
PICKAUTO: Controls automatic windowing at the Select Objects prompt
PICKBOX: Sets the object selection target height, in pixels
PICKDRAG: Controls the method of drawing a selection window
PICKFIRST: Controls whether you select objects before (noun-verb selection) or after you issue a command