Summary of the usage of document.execcommand of

Case 1:
IsNaN tests whether the input is numeric or not, and limits the input to a numeric value such as 1981.121, allowing a maximum of one decimal point

<input type="text" name="text" onkeyup="if(isNaN(value))execCommand('undo')" />

<input type=button value= shear  onclick=document.execCommand('Cut')>
<input type=button value= copy  onclick=document.execCommand('Copy')>
<input type=button value= paste  onclick=document.execCommand('Paste')>
<input type=button value= undo  onclick=document.execCommand('Undo')>
<input type=button value= redo  onclick=document.execCommand('Redo') id=button2 name=button2>
<input>
<input type=button value= delete  onclick=document.execCommand('Delete')>
<input type=button value= blackbody  onclick=document.execCommand('Bold')>
<input type=button value= italics  onclick=document.execCommand('Italic')>
<input type=button value= The underline  onclick=document.execCommand('Underline')>
<input type=button value= stop  onclick=document.execCommand('stop')>
<input type=button value= save  onclick=document.execCommand('SaveAs')>
<input type=button value= Save as  onclick=document.execCommand('Saveas',false,'c:\test.htm')>
<input type=button value= The font  onclick=document.execCommand('FontName',false,fn)>
<input type=button value= The font size  onclick=document.execCommand('FontSize',false,fs)>
<input type=button value= The refresh  onclick=document.execCommand('refresh',false,0)>