1.首先呢我们要根据ID来进行一个查询
var sql = "select * from Product where id=" + id;
2.我们把查询到的放在一个DataTable对象内。（且大于查询结果大于1，小于1的话返回空）
DataTable dt = SqlHelper.Cx(sql); if (dt.Rows.Count<1) { return null; }
3.把查询到的行放入DataRow对象。然后返回这个信息
DataRow row = dt.Rows[0]; return new Product() { ProductName = row["ProductName"].ToString(), MarketPrice = Convert.ToDouble(row["MarketPrice"]), SellingPrice = Convert.ToDouble(row["SellingPrice"]), CategoryId = Convert.ToInt32(row["CategoryId"]), Introduction = Convert.ToString(row["Introduction"]), IsOnSale = Convert.ToInt32(row["IsOnSale"]), Addtime = Convert.ToString(row["Addtime"]), };
我们看下整体代码：
public static Product Select(int id) { var sql = "select * from Product where id=" + id; DataTable dt = SqlHelper.Cx(sql); if (dt.Rows.Count<1) { return null; } DataRow row = dt.Rows[0]; return new Product() { ProductName = row["ProductName"].ToString(), MarketPrice = Convert.ToDouble(row["MarketPrice"]), SellingPrice = Convert.ToDouble(row["SellingPrice"]), CategoryId = Convert.ToInt32(row["CategoryId"]), Introduction = Convert.ToString(row["Introduction"]), IsOnSale = Convert.ToInt32(row["IsOnSale"]), Addtime = Convert.ToString(row["Addtime"]), }; }
这就是我们根据ID来查询行信息的方法~
原文：https://www.cnblogs.com/NeatFan/p/13181280.html