在textarea的光标处插入值
var textArea=Ext.getCmp(textAreaId);var o = Ext.getDom(textAreaId); //The text box to be inserted o.focus(); var s = document.selection.createRange();//以先保存选区的方式用于在IE中实现插入 var value = flag; if (document.selection) {//用于IE s.text = value; s.moveEnd('character',value.length); s.moveStart('character',value.length); } else {//用于FF o.value = o.value.substr(0, o.selectionStart) + value + o.value.substr(o.selectionEnd); }