Insert integer when dropdownlist displays strings as datavaluefield

问题

• i am developing my app on visual studio 2008
• i have 4 tables
• i have a dropdownlist (displays product_category_names)
• i need to do an insert statement

• i have the following code:

  Dim sql2 As String = "INSERT INTO Product (product_category_id, product_name, product_title, product_desc, product_author, product_author_age, product_author_desc, product_other_detail, product_dimension1, product_dimension2, product_price, product_institution, product_status, product_delivery_time) VALUES (@product_category_id, @product_name, @product_title, @product_desc, @product_author, @product_author_age, @product_author_desc, @product_other_detail, @product_dimension1, @product_dimension2, @product_price, @product_institution, @product_status, @product_delivery_time)"

cmd.Parameters.Add(New SqlParameter("@product_name", (txtProductName2.Text))) cmd.Parameters.Add(New SqlParameter("@product_title", (txtProductTitle2.Text)))

Question is, how may I insert 'product_category_id' (an Integer) into the table 'Product', when the dropdownlist displays 'product_category_names' instead of 'product_category_id'?

Can someone show me the light? Thanks.

回答1:

Assuming you are binding your dropdownlist on the page load event and using the product_Catogry table then The easiest way would be to bind product_category_ID to the value property of the dropdownlist. This way you can programatically access the ID while the user sees the name.

DropDownList.DataSource = [your product table]
DropDownList.DataTextField = "Proudct_Category_Name"
DropDownList.DataValueField = "Product_category_ID"

If this is not an option for whatever reason then the below SQL will work in your current command, just make sure you add @Product_Category_Name as a parameter to the SqlCommand instead of @product_Category_Name.

INSERT INTO Product 
(       product_category_id, 
        product_name, 
        product_title, 
        product_desc, 
        product_author, 
        product_author_age, 
        product_author_desc, 
        product_other_detail, 
        product_dimension1, 
        product_dimension2, 
        product_price, 
        product_institution, 
        product_status, 
        product_delivery_time
)    
SELECT  product_category_id, 
        @product_name, 
        @product_title, 
        @product_desc, 
        @product_author, 
        @product_author_age, 
        @product_author_desc, 
        @product_other_detail, 
        @product_dimension1, 
        @product_dimension2, 
        @product_price, 
        @product_institution, 
        @product_status, 
        @product_delivery_time
FROM    product_category
WHERE   product_category_Name = @Product_Category_Name

Or you could simply add this to the start of your current SQL:

DECLARE  @Product_Category_ID INT
SELECT   @Product_Category_ID = Product_Category_ID
FROM     Product_Category
WHERE    Product_Category_Name = @Product_Category_Name

And continue with the insert ... values ().

来源：https://stackoverflow.com/questions/9043348/insert-integer-when-dropdownlist-displays-strings-as-datavaluefield