获得TextBox中光标的位置(get the cursor position in a TextBox or InputText)

使用JavaScript实现：

 

function  getposition()
{
         var  txt1 = document.getElementById( " TextBox1 " );
    
         var  currentRange = document.selection.createRange();   
         var  workRange = currentRange.duplicate();
        txt1.select();
         var  allRange = document.selection.createRange();
         var  len = 0 ;   
    
         while (workRange.compareEndPoints( " StartToStart " ,allRange) > 0 )   
        {   
          workRange.moveStart( " character " , - 1 );   
          len ++ ;   
        }   
    
        currentRange.select();   
        
        window.alert(len); 
}