Gridview更新(不起作用) [英] Gridview update(not functioning)

问题描述

我有这段代码，并且在运行期间收到错误，提示为没有为一个或多个参数提供值"

I have this code and I get the error during the run as "No value given for one or more parameters"

string updateSql = "UPDATE RateCenters SET RateCenterName = @RateCenterName, Province= 
@Province, QuantityThreshold = @QuantityThreshold" + "WHERE RateCenterID= @RateCenterID";


    protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {                    
        GridViewRow row = (GridViewRow)GridView1.Rows[e.RowIndex];

        DropDownList ddl = (DropDownList)row.FindControl("DropDownList2"); // assigning the dropdownlist item to 'ddl'

        TextBox rateCenterName = (TextBox)row.FindControl("txtRateCenterName"); // assigning textbox input item

        TextBox quantityThreshold = (TextBox)row.FindControl("txtQuantityThreshold"); // assigning textbox input item

        Label ratecenterid = (Label)row.FindControl("Label1"); // assigning the label value

     //  OleDbConnection conn = new OleDbConnection(ConfigurationManager.ConnectionStrings["DBConnection"].ToString());

        OleDbConnection conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Documents and Settings\arjun.giridhar\My Documents\Visual Studio 2010\Projects\BillingApplicationNew\BillingApplicationNew\App_Data\db1.mdb;Persist Security Info=False");

        OleDbCommand cmd = null;

        try
        {


            cmd = new OleDbCommand(updateSql, conn);


            cmd.Parameters.Add("RateCenterName", OleDbType.VarChar).Value = rateCenterName.Text;
            cmd.Parameters.Add("Province", OleDbType.VarChar).Value = ddl.SelectedItem.Text;
            cmd.Parameters.Add("QuantityThreshold", OleDbType.Integer).Value = Convert.ToUInt32(quantityThreshold.Text);
            cmd.Parameters.Add("RateCenterID", OleDbType.Integer).Value = Convert.ToInt32(ratecenterid.Text);


            conn.Open();
            cmd.Connection = conn;
            cmd.ExecuteNonQuery();

            //GridView1.EditIndex = -1; //refreshing
            //GridView1.DataBind();
        }

        catch (OleDbException ex)
        {
            throw (ex);
        }

        finally
        {

            conn.Close();
            conn.Dispose();
        }
    }

读取了值，但我希望它不会被存储在cmd.parameter语句中的@xxxxxx中
请帮助我

问候，Arjun

values are read but I hope it is not getting stored in @xxxxxx in cmd.parameter statement

kindly help me out

regards, Arjun

推荐答案

您正在使用oledbcommand不能使用的命名参数.您需要使用吗? char作为参数，当您在命令参数集合中添加参数时，您需要按正确的顺序添加它们，就像查询中有参数一样.

示例:

Hi,

You are using named parameters which is not possible with oledbcommand. You need to use ? char for parameters, and when you add parameters in command parameters collection you need to add them in proper order like you have parameters in your query...

Example:

string updateSql = "UPDATE RateCenters SET RateCenterName = ?, Province= 
?, QuantityThreshold = ? WHERE RateCenterID= ?";

// ...
OleDbParameter p1 = new OleDbParameter();
OleDbParameter p2 = new OleDbParameter();
OleDbParameter p3 = new OleDbParameter();
OleDbParameter p4 = new OleDbParameter();

p1.Value = "RateCenterName ";
p2.Value = "Province";
p3.Value = "QuantityThreshold ";
p2.Value = "RateCenterID";

cmd.Parameters.Add(p1);
cmd.Parameters.Add(p2);
cmd.Parameters.Add(p3);
cmd.Parameters.Add(p4);

// ...

添加参数时，您需要按命令中的顺序对其进行添加...

该代码可能有错误，并且提供该代码只是为了显示我的意思...

While adding parameters you need to add them in order like they are in command...

The code maybe have errors and its provided just to show what I mean...

在下面的查询中使用:

Hi, use below query:

string updateSql = "UPDATE RateCenters SET RateCenterName = @RateCenterName, Province=
@Province, QuantityThreshold = @QuantityThreshold" + " WHERE RateCenterID= @RateCenterID";

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