ASP.NET中存储db值的问题 [英] Problem in ASP.NET to store db values

问题描述

我在SQl中占了一张桌子floor哪些列像''id''自动生成和''name''。在那里我插入3个值，如一个，两个，三个。



我的问题是;

i想要读取数据库中的3个值并显示与3个值相关的3个图像。



我的代码是这样的。

Hi,

I have take one table in SQl "floor" which columns like ''id'' autogenerated and ''name''. And in that i insert 3 values like "one","two","three".

My question is ;
i want to read that 3 values from database and related to that three values disply 3 images.

My code like this.

string str;
        con.Open();
        cmd = new SqlCommand("Select name from floor",con);
        SqlDataReader dr = cmd.ExecuteReader();


        while (dr.Read())
        {
            str = Convert.ToString(dr["name"].ToString());
            if (str == "one" && str=="two" && str=="three")
            {
                Image1.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_101_booked.png";
                Image2.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_102.png";
                Image3.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_103.png";
              
            }
        }
        con.Close();

但我不明白如果条件如何使用。



求助。我在等。

But I am not understand how to use that if condition.

Pleases help. I am waiting.

推荐答案

你的逻辑语句永远不会是真的....

str变量只能是其中一个值所有这三个。

your logical statement will never be true....
str variable can only be one of the values not all three of them.

if (str == "one" && str=="two" && str=="three")

你可能想要的是

what you probably want is

if (str == "one") 
    Image1.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_101_booked.png"; 
else if (str == "two")
    Image2.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_102.png";
else if (str == "three")
    Image3.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_103.png";

或者这个

Or this

if (str == "one" || str=="two" || str== "three")
{
    Image1.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_101_booked.png";
    Image2.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_102.png";
    Image3.ImageUrl = "~/images/book_flat_imgs/AWing/first_floor/A_103.png";
}

通常会读取c＃运算符和逻辑运算符以了解您的代码正在做什么。

http://msdn.microsoft.com/en-us/library/6a71f45d(v=vs .71）.aspx [ ^ ]

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