Exception thrown: 'System.Data.SqlClient.SqlException' in System.Data.dll Additional infor-CodePudding

This Is My Codding i have face this type of error in my code (Exception thrown: 'System.Data.SqlClient.SqlException' in System.Data.dll

Additional information: Error converting data type varchar to bigint.)

Update Query:___________________________________

private void btnUpdate_Click(object sender, EventArgs e)

    {
        query = ("update items set name='"   txtName.Text   "',category='"   txtCategory.Text   "',price='"   txtPrice.Text   "where iid ="   id   "'");
        fn.setData(query);
        loadData();
        txtName.Clear();
        txtCategory.Clear();
        txtPrice.Clear();
    }

Set Query_______________

public void setData(String query)

    {
        SqlConnection con = getConnection();
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        con.Open();
        cmd.CommandText = query;
        cmd.ExecuteNonQuery();
        con.Close();


        MessageBox.Show("Data Processed Successfully.", "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);

    }

CodePudding user response：

Always try to use Parameterized Query or Stored Procedure, rather than injecting values.

btnUpdate_Click

private void btnUpdate_Click(object sender, EventArgs e)
{
    query = ("update items set name = @name, category = @category, price = @price where iid = @id");
    fn.setData(query);
    loadData();
    txtName.Clear();
    txtCategory.Clear();
    txtPrice.Clear();
}

setData function

public void setData(String query)
{
    SqlConnection con = getConnection();
    SqlCommand cmd = new SqlCommand();
    cmd.Connection = con;
    cmd.CommandText = query;
    cmd.Parameters.AddWithValue("@name", txtName.Text);
    cmd.Parameters.AddWithValue("@category", txtCategory.Text);
    cmd.Parameters.AddWithValue("@price", txtPrice.Text);
    cmd.Parameters.Add(new SqlParameter()
    {
        DbType = System.Data.DbType.Int64, //For big int
        Direction = System.Data.ParameterDirection.Input,
        ParameterName = "@id",
        Value = Convert.ToInt64(id)
    });
    try
    {
        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
        MessageBox.Show("Data Processed Successfully.", "Success",MessageBoxButtons.OK, MessageBoxIcon.Information);
    }
    catch(Exception ex)
    {
        // catch exception here
    }
}

CodePudding user response：

Change your code as highlighted below, it should solve your problem.

{

query = ("update items set name='" txtName.Text "',category='" txtCategory.Text "',price= " int.Parse(txtPrice.Text) "where iid =" id "'");

    fn.setData(query);
    loadData();
    txtName.Clear();
    txtCategory.Clear();
    txtPrice.Clear();
}