的ExecuteScalar（）;随着SCOPE_IDENTITY（）生成＆QUOT; System.InvalidCastException：指定强制转换为无效＆QUOT;

本文介绍了的ExecuteScalar（）;随着SCOPE_IDENTITY（）生成＆QUOT; System.InvalidCastException：指定强制转换为无效＆QUOT;的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 我已经拥有它接受各种数据（通过文本框和的CheckBoxList）的一种形式，在click事件，他们插入所有的数据到一个表，然后选择在SCOPE_IDENTITY其存储在一个变量来使用它的插入使用循环的CheckBoxList项目到另一个表据许多答案和例子，这应该很好地工作..但它给了我这个错误： 异常详细信息：System.InvalidCastException：指定强制转换为无效。第66行：INT NewBrandId =（INT）comm.ExecuteScalar（）; 下面是我的LinkBut​​ton方法code： 保护无效lnkbtnUploadAndSubmit_Click（对象发件人，EventArgs的）    {        SqlConnection的康恩=新的SqlConnection（ConfigurationManager.ConnectionStrings [MOODbCenterConnection]的ConnectionString。）;        SqlCommand的通讯=新的SqlCommand（INSERT INTO品牌（名优产品，BrandLogo，BrandWebsite，IsBrandVisible）VALUES（@Name，@Logo，@Website，@IsVisible）;选择SCOPE_IDENTITY（）;，康涅狄格州）;        comm.Parameters.Add（@名称，System.Data.SqlDbType.NVarChar，50）;        。comm.Parameters [@名]值= txtbxBrandName.Text;        comm.Parameters.Add（@标志，System.Data.SqlDbType.Text）;        comm.Parameters [@标志]值= fileuploadLogo.PostedFile.FileName。        comm.Parameters.Add（@网站，System.Data.SqlDbType.Text）;        comm.Parameters [@网站]值= txtbxWebsite.Text。        comm.Parameters.Add（@可见性，System.Data.SqlDbType.Bit）;        。comm.Parameters [@可见性]值= chkbxIsPublished.Checked;        conn.Open（）;        INT NewBrandId =（INT）comm.ExecuteScalar（）;        conn.Close（）;        的foreach（在chkbxlstCuisines.Items列表项丽）        {            如果（li.Selected）            {                conn.Open（）;                SqlCommand的COMM2 =新的SqlCommand（INSERT INTO BrandCuisines（CuisineId，BrandId）VALUES（@CuisineId，@NewBrandId），康涅狄格州）;                comm2.Parameters.Add（@ CuisineId，System.Data.SqlDbType.Int）;                comm2.Parameters [@ CuisineId]值= li.Value。                comm2.Parameters.Add（@ NewBrandId，System.Data.SqlDbType.Int）;                comm2.Parameters [@ NewBrandId]值= NewBrandId。                comm2.ExecuteNonQuery（）;                conn.Close（）;            }        }    } 编辑奇怪的查询工作正常，当我直接在Visual Studio中的SQL服务器EX preSS运行它！ 怪异的解释这个奇怪的问题 首先解决由alexb： 例：INT NewBrandId = System.Convert.ToInt32（comm.ExecuteScalar（））; 由我第二个解决方法：谢谢你们，我希望它帮助别人！解决方案 究竟 comm.ExecuteScalar（）的回报？也许它返回长或双包装成对象。记不太清了，但好像我曾面临一些1-2年前。 I've have a form which accept various data (through textboxes and a checkboxlist) and on the click event they insert all the data into a table and selects the scope_identity then store it in a variable to use it in the insertion of the checkboxlist items using a loop into another tableaccording to many answers and examples this should work perfectly!..but it gives me this error :Exception Details: System.InvalidCastException: Specified cast is not valid.Line 66: int NewBrandId = (int)comm.ExecuteScalar(); Here's my linkbutton method code : protected void lnkbtnUploadAndSubmit_Click(object sender, EventArgs e) { SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["MOODbCenterConnection"].ConnectionString); SqlCommand comm = new SqlCommand("INSERT INTO Brands (BrandName, BrandLogo, BrandWebsite, IsBrandVisible) VALUES (@Name, @Logo, @Website, @IsVisible); SELECT scope_identity();", conn); comm.Parameters.Add("@Name", System.Data.SqlDbType.NVarChar, 50); comm.Parameters["@Name"].Value = txtbxBrandName.Text; comm.Parameters.Add("@Logo", System.Data.SqlDbType.Text); comm.Parameters["@Logo"].Value = fileuploadLogo.PostedFile.FileName; comm.Parameters.Add("@Website", System.Data.SqlDbType.Text); comm.Parameters["@Website"].Value = txtbxWebsite.Text; comm.Parameters.Add("@IsVisible", System.Data.SqlDbType.Bit); comm.Parameters["@IsVisible"].Value = chkbxIsPublished.Checked; conn.Open(); int NewBrandId = (int)comm.ExecuteScalar(); conn.Close(); foreach (ListItem li in chkbxlstCuisines.Items) { if (li.Selected) { conn.Open(); SqlCommand comm2 = new SqlCommand("INSERT INTO BrandCuisines (CuisineId, BrandId) VALUES (@CuisineId, @NewBrandId)", conn); comm2.Parameters.Add("@CuisineId", System.Data.SqlDbType.Int); comm2.Parameters["@CuisineId"].Value = li.Value; comm2.Parameters.Add("@NewBrandId", System.Data.SqlDbType.Int); comm2.Parameters["@NewBrandId"].Value = NewBrandId; comm2.ExecuteNonQuery(); conn.Close(); } } }Edit Strangely the query works fine when I run it directly in the sql server express of the visual studio!THE Weird Explanation For This Weird Problem First Solution by alexb : Example : int NewBrandId = System.Convert.ToInt32(comm.ExecuteScalar());Second Solution by me :Thanks guys and I hope it help others! 解决方案 What exactly comm.ExecuteScalar() returns? Maybe it returns long or double packed into object.can't remember exactly, but seems like I had faced something 1-2 years ago. 这篇关于的ExecuteScalar（）;随着SCOPE_IDENTITY（）生成＆QUOT; System.InvalidCastException：指定强制转换为无效＆QUOT;的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！