var TT = {
/*
* 獲取光標位置
* @Method getCursorPosition
* @param t element
* @return number
*/
getCursorPosition: function(t){
if (document.selection) {
t.focus();
var ds = document.selection;
var range = ds.createRange();
var stored_range = range.duplicate();
stored_range.moveToElementText(t);
stored_range.setEndPoint("EndToEnd", range);
t.selectionStart = stored_range.text.length - range.text.length;
t.selectionEnd = t.selectionStart + range.text.length;
return t.selectionStart;
} else return t.selectionStart
},
/*
* 設置光標位置
* @Method setCursorPosition
* @param t element
* @param p number
* @return
*/
setCursorPosition:function(t, p){
this.sel(t,p,p);
},
/*
* 插入到光標后面
* @Method add
* @param t element
* @param txt String
* @return
*/
add:function (t, txt){
var val = t.value;
if(document.selection){
t.focus()
document.selection.createRange().text = txt;
} else {
var cp = t.selectionStart;
var ubbLength = t.value.length;
var s = t.scrollTop;
// document.getElementById('aaa').innerHTML += s + '<br/>';
t.value = t.value.slice(0,t.selectionStart) + txt + t.value.slice(t.selectionStart, ubbLength);
this.setCursorPosition(t, cp + txt.length);
// document.getElementById('aaa').innerHTML += t.scrollTop + '<br/>';
firefox=navigator.userAgent.toLowerCase().match(/firefox//([/d/.]+)/) && setTimeout(function(){
if(t.scrollTop != s) t.scrollTop=s;
},0)
};
},
/*
* 刪除光標 前面或者后面的 n 個字符
* @Method del
* @param t element
* @param n number n>0 后面 n<0 前面
* @return
* 重新設置 value 的時候 scrollTop 的值會被清0
*/
del:function(t, n){
var p = this.getCursorPosition(t);
var s = t.scrollTop;
var val = t.value;
t.value = n > 0 ? val.slice(0, p - n) + val.slice(p):
val.slice(0, p) + val.slice(p - n);
this.setCursorPosition(t ,p - (n < 0 ? 0 : n));
firefox=navigator.userAgent.toLowerCase().match(/firefox//([/d/.]+)/) && setTimeout(function(){
if(t.scrollTop != s) t.scrollTop=s;
},10)
},
/*
* 選中 s 到 z 位置的文字
* @Method sel
* @param t element
* @param s number
* @param z number
* @return
*/
sel:function(t, s, z){
if(document.selection){
var range = t.createTextRange();
range.moveEnd('character', -t.value.length);
range.moveEnd('character', z);
range.moveStart('character', s);
range.select();
}else{
t.setSelectionRange(s,z);
t.focus();
}
},
/*
* 選中一個字符串
* @Method sel
* @param t element
* @param s String
* @return
*/
selString:function(t, s){
var index = t.value.indexOf(s);
index != -1 ? this.sel(t, index, index + s.length) : false;
}
}