input string was not in correct format .....

Question

public partial class checkbox4 : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { GridView1.DataSource = SqlDataSource1; GridView1.DataBind(); } } protected void Button1_Click(object sender, EventArgs e) { foreach (GridViewRow row in GridView1.Rows) { CheckBox status = (row.Cells[3].FindControl("CheckBox1") as CheckBox); int app_id = Convert.ToInt32(row.Cells[1].Text); if (status.Checked) { updaterow(app_id, "A"); } else { updaterow(app_id, "N"); } } Label1.Text = "Applications Has Been Approved Successfully"; SqlDataSource1.DataBind(); GridView1.DataSource = SqlDataSource1; GridView1.DataBind(); } private void updaterow(int app_id, String status) { String mycon = "Data Source=DESKTOP-F60JREG\SQLEXPRESS;Initial Catalog=testhrm;Integrated Security=True"; String updatedata = "Update tbl_data set status='" + status + "' where id=" + app_id; SqlConnection con = new SqlConnection(mycon); con.Open(); SqlCommand cmd = new SqlCommand(); cmd.CommandText = updatedata; cmd.Connection = con; cmd.ExecuteNonQuery(); } }

Jignesh Kumar · Answer

Hi Noms,   Please check below two places, first one when are converting app_id and second one when you are checking Checkbox status.checked, you should check for status control is null or not. foreach (GridViewRow row in GridView1.Rows) { CheckBox status = (row.Cells[3].FindControl( "CheckBox1" ) as CheckBox); int app_id = ! string .IsNullOrEmpty(row.Cells[1].Text) ? Convert.ToInt32(row.Cells[1].Text) : 0; if (status != null ) { if (status.Checked) { updaterow(app_id, "A" ); } else { updaterow(app_id, "N" ); } }

Sagar Malde · Answer

It seems C#'s conversion exception. This occure when you are trying to convert a value to another data type but that value is improper to convert.   I think the issue is in the following line    int  app_id = Convert.ToInt32(row.Cells[1].Text);    Check what value is in row.Celss[1].Text. That value should be in numbers not decimal neither float just a simple number.

Jaish Mathews · Answer

It seems SQL query type format issue. What are types of table columns status and id? Also what are types for variables status and app_id in C# code?

Rajeesh Menoth · Answer

Hi,   First of all put a break point and identify the exact line of the error. I have one suggestion on your code better to use "Parameterized queries" to avoid sql injection.   Reference :   https://stackoverflow.com/questions/7505808/why-do-we-always-prefer-using-parameters-in-sql-statements

Noms Nom · Answer

kindly tell me what i have to do