how to end a prompting select entity operation ?

[giser828DUHJV]

my modeless dialog has two buttons,  the first button clicked to prompt select  an entity,

if the second button clicked , i want to end the prompting select entity first and then  do other things，

how  to  end the prompting select entity  operation in the second button click event ?

[ActivistInvestor]

You can use the Document's SendStringToExecute() method to send an escape sequence to the command line. 

[giser828DUHJV]

doc.SendStringToExecute("\x03\x03", false, true, false);   ?

// this operation will change the entities selected state 

[ActivistInvestor]

Yes, it will deselect entities.  The only other option is to add a keyword to your prompt, and issue the keyword using SendStringToExecute().