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POmy c# code throws an exception on accessing sql server
 

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  1. POmy c# code throws an exception on accessing sql server
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    <p>i am new to c# and sql I am creating a simple student database I added my database created in sql server 2008. now i have a form where the inputs are given and i have a button insert to insert the data into the database. But when i click the button i get an exception.</p> <p>this is my App.config file</p> <pre><code>`&lt;?xml version="1.0" encoding="utf-8" ?&gt; &lt;configuration&gt; &lt;startup&gt; &lt;supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" /&gt; &lt;/startup&gt; &lt;configSections&gt; &lt;connectionStrings&gt; &lt;appSettings&gt; &lt;add name="ConString" connectionString="Data Source=ARAVIND-HP\SQLEXPRESS; Initial Catalog=test;Integrated Security=True" providerName="System.Data.sqlClient"/&gt; &lt;/appSettings&gt; &lt;/connectionStrings&gt; </code></pre> <p> `</p> <p>The form i used is given below</p> <pre><code>using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace test { public partial class frmNewStudent : Form { public frmNewStudent() { InitializeComponent(); } private void btnClose_Click(object sender, EventArgs e) { this.Close(); } private void frmNewStudent_Load(object sender, EventArgs e) { } private void btnInsert_Click(object sender, EventArgs e) { DB_Access access = new DB_Access(); access.add_student(txtRegNo.Text,txtFName.Text,txtLName.Text,txtPhone.Text); MessageBox.Show("Data added successfully"); } } } </code></pre> <p>now i have two classes 1.DB_access 2.DB_Connections</p> <p>the code of DB_access is below</p> <pre><code>using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data; using System.Configuration; using System.Data.SqlClient; namespace test { class DB_Access { public SqlConnection conn; public DB_Access() { conn = DB_Connection.GetConnection(); } public void add_student(string regno, string fname, string lname, string phone) { if(conn.State.ToString()=="Closed") { conn.Open(); } SqlCommand newCmd = conn.CreateCommand(); newCmd.Connection = conn; newCmd.CommandType = CommandType.Text; newCmd.CommandText = "insert into student values('"+ regno +"','"+ fname +"','"+ lname +"','"+ phone +"')"; newCmd.ExecuteNonQuery(); } } } </code></pre> <p>the code of DB_Connections is below</p> <pre><code>using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data; using System.Configuration; using System.Data.SqlClient; namespace test { class DB_Connection { public static SqlConnection NewCon; public static string ConStr = ConfigurationManager.ConnectionStrings["ConString"].ConnectionString; public static SqlConnection GetConnection() { NewCon = new SqlConnection(ConStr); return NewCon; } } } </code></pre> <p>when i run this and when i click the insert button i get the following exception:</p> <p>An unhandled exception of type 'System.TypeInitializationException' occurred in test.exe</p> <p>Additional information: The type initializer for 'test.DB_Connection' threw an exception.</p> <p>and the line 'conn = DB_Connection.GetConnection();' gets highlighted</p> <p>i am not able to find the error.please help me with this</p>
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    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. USAravind Bharathy
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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      1. PTAnswer
    2. PO
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      1. PTAnswer
    3. PO
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      1. PTAnswer
    1. VO
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      1. POmy c# code throws an exception on accessing sql server
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
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      1. POmy c# code throws an exception on accessing sql server
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
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      1. POmy c# code throws an exception on accessing sql server
      1. This table or related slice is empty.
      1. VTUpMod
    1. CO`conn.State.ToString()=="Closed"`??? Yuck!! Use `conn.State == ConnectionState.Closed`...
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      1. POmy c# code throws an exception on accessing sql server
      1. USThorsten Dittmar
    2. CObut this is not solving the problem
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      1. POmy c# code throws an exception on accessing sql server
      1. USAravind Bharathy
    3. CONo, this doesn't solve the problem - that's why I wrote a comment, not an answer.
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      1. POmy c# code throws an exception on accessing sql server
      1. USThorsten Dittmar
 

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