Delete button code using checkbox

Question

// Delete Button Details// private void button3_Click ( object sender  EventArgs e ) { iselibraryEntities ise = new iselibraryEntities (); foreach ( var item in dataGridView1 . Rows ) { DataGridViewRow row = item as DataGridViewRow ; if ( row . Selected ) { string usn = row . Cells [ USN ]. Value . ToString (); var issu = ise . T_BOOK_ISSUE_TABLE . FirstOrDefault ( a => a . USN . Equals ( usn )); if ( issu != null ) { ise . T_BOOK_ISSUE_TABLE . remove } } } Thing is I don't get a dropdown for remove in if loop after ise.T_BOOK_ISSUE_TABLE . Error says as 'Object Query ' does not contain a definition for 'remove' and no extension method 'remove' accepting a first argument of type'Object Query 'could be found(are you missing a directive or an assembly reference?)

Sujeet Suman · Answer

Please once go through below link & make secure you are following all steps: http://www.codeproject.com/Articles/37932/Simple-Sample-with-Entity-Framework

Bharthish Athreya · Answer

T_BOOK_ISSUE_TABLE is table name and iselibraryentities is Data context name after adding ADO.net Entity Data model.

Sujeet Suman · Answer

Bharthish can you please clear that what is  iselibraryEntities &  T_BOOK_ISSUE_TABLE?

Bharthish Athreya · Answer

complete code is given below please let me know where should i add your first(1. makes sure you have written this public DbSet T_BOOK_ISSUE_TABLE { get; set; } in your context class) solution in my code.Thank you Ravi Patel sir. Code as follows: using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Data.SqlClient; namespace Iselibrary { public partial class Delete : Form { SqlConnection vid = new SqlConnection(Data Source=.;Initial Catalog=iselibrary;Integrated Security=True); //private object item; public Delete() { InitializeComponent(); } private void bindingNavigatorDeleteItem_Click(object sender EventArgs e) { } private void button1_Click_1(object sender EventArgs e) { this.Close(); Home home = new Home(); home.Show(); } private void Update_Load(object sender EventArgs e) { // TODO: This line of code loads data into the 'iselibraryDataSet1.T_BOOK_ISSUE_TABLE' table. You can move or remove it as needed. this.t_BOOK_ISSUE_TABLETableAdapter.Fill(this.iselibraryDataSet1.T_BOOK_ISSUE_TABLE); } private void button2_Click(object sender EventArgs e) { String str = Select * from T_BOOK_ISSUE_TABLE where (USN like '%' + @search + '%'); SqlCommand xp = new SqlCommand(str vid); xp.Parameters.Add(@search SqlDbType.NVarChar).Value = textBox1.Text; vid.Open(); xp.ExecuteNonQuery(); SqlDataAdapter da = new SqlDataAdapter(); da.SelectCommand = xp; DataSet dat = new DataSet(); da.Fill(dat USN); dataGridView1.DataSource = dat; dataGridView1.DataSource = dat.Tables[0]; vid.Close(); } private void textBox1_TextChanged(object sender EventArgs e) { } // Delete Button Details// private void button3_Click(object sender EventArgs e) { iselibraryEntities ise = new iselibraryEntities(); foreach (var item in dataGridView1.Rows) { DataGridViewRow row = item as DataGridViewRow; if (row.Selected) { string usn = row.Cells[USN].Value.ToString(); var issu = ise.T_BOOK_ISSUE_TABLE.FirstOrDefault(a => a.USN.Equals(usn)); if (issu != null) { ise.T_BOOK_ISSUE_TABLE.Remove /* as error occurs here I have not completed the code */ } } } } private void dataGridView1_CellContentClick(object sender DataGridViewCellEventArgs e) { } } } THANK YOU

Ravi Patel · Answer

Hi Bharthish check two things 1. makes sure you have written this public DbSet T_BOOK_ISSUE_TABLE { get; set; } in your context class 2. ise.T_BOOK_ISSUE_TABLE. Remove(issu) means change it from remove() to Remove() may be it helps you

Bharthish Athreya · Answer

Sujeet Suman SirThat code also didn't work because I don't get remove option as soon as after tablename.Remove Remove option is not accepting. I have also mentioned the error. Thank you

Sujeet Suman · Answer

Bharthish please once try below code? private void button3_Click(object sender EventArgs e) { iselibraryEntities ise = new iselibraryEntities(); foreach(var item in dataGridView1.Rows) { DataGridViewRow row = item as DataGridViewRow; if(row.Selected) { string usn = row.Cells[USN].Value.ToString(); var issu = ise.T_BOOK_ISSUE_TABLE.FirstOrDefault(a => a.USN.Equals(usn)); if(issu!=null) { ise.T_BOOK_ISSUE_TABLE.remove( issu ) ; ise.SaveChanges(); } } } } If this is helpful for you then please accept my Answer .