javascript javascript加载类似星座、血型的函数

//加载血型
function bloodtypelaod(constellation) {
var obj = document.getElementById('bloodtype');
obj.options.length = 0;
var option = document.createElement("option");
option.value = "0";
option.text = "请选择";
obj.add(option);

var arr = new Array("A型", "B型", "AB型", "O型");
for (var i = 0; i < arr.length; i++) {
option = document.createElement("option");
option.value = i + 1;
option.text = arr[i];
if (constellation == arr[i]) {
option.selected = true;
}
obj.add(option);
}
}