利用js在文本框末尾获得焦点

function moveEnd(obj) {
obj.focus();
var len = obj.value.length;
if (document.selection) {
var sel = obj.createTextRange();
sel.moveStart('character', len);
sel.collapse();
sel.select();
} else if (typeof obj.selectionStart == 'number'
&& typeof obj.selectionEnd == 'number') {
obj.selectionStart = obj.selectionEnd = len;
}
}