//格式化小数
function formatTwo(x) {
 var f_x = parseFloat(x);
 if (isNaN(f_x)) {
 alert('function:formatTwo->parameter error');
 return false;
 }
 var f_x = Math.round(x * 100) / 100;
 var s_x = f_x.toString();
 var pos_decimal = s_x.indexOf('.');
 if (pos_decimal < 0) {
 pos_decimal = s_x.length;
 s_x += '.';
 }
 while (s_x.length <= pos_decimal + 2) {
 s_x += '0';
 }
 return s_x;
}