您可以使用临时容器(例如HashSet)并将所有元素添加到其中.最后，将HashSet的数据复制到ArrayList.

干杯..

You can use a temporary container such as HashSet and adding all element to it. Finally copy the data of HashSet to ArrayList.

Cheers..

ArrayList ar = new ArrayList();

for (int h = 0; h<ds1.Tables[0].Rows.Count; h++)
{
    if (!ar.Contains(ds1.Tables[0].Rows[h][0].ToString()))
    {
        ar.Add(Convert.ToString(ds1.Tables[0].Rows[h][0].ToString()));
    }
}