如何从表中删除

本文介绍了如何从表中删除的处理方法，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 嘿，我想删除一个选定的工作人员（显示在列表框中）/我的代码

private void button2_Click（ object sender，EventArgs e） { SqlConnection con = new SqlConnection（ 数据源= JAMES-PC\\SQLEXPRESS;初始目录=员工;集成安全性=真）; con.Open（）; string sql = @ DELETE FROM staff1其中Id = @ name;; SqlCommand cmd = new SqlCommand（sql，con）; cmd.Parameters.AddWithValue（ @ name， 1 ）; cmd.ExecuteNonQuery（）; con.Close（）; }

但是当我运行程序时，我点击按钮（删除）但是没有运气，没有删除它 任何帮助将不胜感激 列表框中显示的表格是（名称）

解决方案

private void button2_Click（ object sender，EventArgs e） { SqlConnection con = new SqlConnection（ 数据源= JAMES-PC\\SQLEXPRESS;初始目录=员工;集成安全性=真）; con.Open（）; string sql = @ DELETE FROM staff1其中Id = @ name;; SqlCommand cmd = new SqlCommand（sql，con）; cmd.Parameters.AddWithValue（ @ name， listBox1.SelectedValue。的ToString（）的）; cmd.ExecuteNonQuery（）; con.Close（）; }

看看参数id是否为varchar，它是这样的： DELETE FROM staff1其中Id ='staff1';

转到Web Config并粘贴此

< connectionStrings > < add name = constring connectionString = 数据source = JAMES-PC\\SQLEXPRESS; initial catalog = staff; persist security info = true; integrated security = true 的providerName = System.Data.SqlClient / > < / connectionStrings >

和chane代码如下

private void button2_Click（object sender，EventArgs e） { SqlConnection con = new SqlConnection（ConfigurationManager.ConnectionStrings [constring ] .ConnectionString）; con.Open（）; string sql = @DELETE FROM staff1 where name = @ name;; SqlCommand cmd = new SqlCommand（DELETE FROM staff1 where name = @ name，con）; cmd.Parameters.AddWithValue（@ name，1）;或//cmd.Parameters.AddWithValue(\"@name，listBox1.SelectedItem.ToString（））; cmd.ExecuteNonQuery（）; con.Close（）; }

始终带id进行删除。谢谢： - ）

hey , i want to delete a selected "staff member" (displayed in listbox) / my code

private void button2_Click(object sender, EventArgs e) { SqlConnection con = new SqlConnection("Data Source=JAMES-PC\\SQLEXPRESS;Initial Catalog=staff;Integrated Security=True"); con.Open(); string sql = @"DELETE FROM staff1 where Id=@name;"; SqlCommand cmd = new SqlCommand(sql, con); cmd.Parameters.AddWithValue("@name", 1); cmd.ExecuteNonQuery(); con.Close(); }

but when i run the program i click the button (remove) but no luck, doesnt delete it any help would be appreciated also the table displayed in the listbox is (name)

解决方案

private void button2_Click(object sender, EventArgs e) { SqlConnection con = new SqlConnection("Data Source=JAMES-PC\\SQLEXPRESS;Initial Catalog=staff;Integrated Security=True"); con.Open(); string sql = @"DELETE FROM staff1 where Id=@name;"; SqlCommand cmd = new SqlCommand(sql, con); cmd.Parameters.AddWithValue("@name", listBox1.SelectedValue.ToString()); cmd.ExecuteNonQuery(); con.Close(); }

see if the parameter id is varchar it is enclosed like this: DELETE FROM staff1 where Id= 'staff1';

Go to Web Config and paste this

<connectionStrings> <add name="constring" connectionString="data source=JAMES-PC\\SQLEXPRESS; initial catalog=staff; persist security info= true; integrated security= true" providerName="System.Data.SqlClient"/> </connectionStrings>

and chane the code as follow

private void button2_Click(object sender, EventArgs e) { SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["constring"].ConnectionString); con.Open(); string sql = @"DELETE FROM staff1 where name=@name;"; SqlCommand cmd = new SqlCommand("DELETE FROM staff1 where name=@name", con); cmd.Parameters.AddWithValue("@name", 1); or //cmd.Parameters.AddWithValue("@name", listBox1.SelectedItem.ToString()); cmd.ExecuteNonQuery(); con.Close(); }

Always go with id for deletion.Thank You:-)