问题
I am using chrome extenstion and want to implement cut copy paste command . In my project i am using canvas . I want to use execCommand function for this . when i implement document.execCommand('copy') and then paste it does not work . i have also changed permission in manifest file . can anybody tell me how this command will work . i tried link http://www.geekpedia.com/tutorial126_Clipboard-cut-copy-and-paste-with-JavaScript.html but document.selection.... is not working undefine error come ?
来源：https://stackoverflow.com/questions/7792139/clipboard-using-chrome-api-execcommand