c# - 林克错误 "Input string was not in a correct format."

Question

我的查询是这样的:

var rport = from exc in db.Exception_Datas
            join emp in db.Emp_infos on exc.Emp_id equals emp.ID
            where (exc.Action_date >= frm && exc.Action_date <= to) && 
                   emp.Branch == cmbBranch.SelectedValue && 
                   emp.Dept == cmbDept.SelectedValue && 
                   emp.ID == Convert.ToInt32(cmbEmp.SelectedValue)
            select new
            {
                emp.Emp_name,
                emp.ID,
                emp.Designation,
                emp.Dept,
                emp.Branch,
                exc.Action_date
            };

我正在签订这样的 cmbEmp.Items:

var allEmp = from emp in db.Emp_infos select emp;
myItem.Text = "--Select--";
myItem.Value = "0";
cmbEmp.Items.Add(myItem);
foreach (var semp in allEmp)
{
    myItem = new RadComboBoxItem();
    myItem.Text = semp.Emp_name.ToString();
    myItem.Value = semp.ID.ToString();
    cmbEmp.Items.Add(myItem);
} 

我关注了其他一些问题，并在 SO 和 SO 之外发帖。但是他们中的任何一个都没有帮助我解决问题。我收到此错误:

{"Input string was not in a correct format."} System.SystemException {System.FormatException}

Answer 1

问题似乎就在这条线上。 Convert.ToInt32(cmbEmp.SelectedValue)。确保它正确解析并在 linq 查询中使用之前解析它。像这样尝试

int empId;

if (Int32.TryParse(cmbEmp.SelectedValue, out empId))
{
    var rport = from exc in db.Exception_Datas
        join emp in db.Emp_infos on exc.Emp_id equals emp.ID
        where (exc.Action_date >= frm && exc.Action_date <= to) && 
               emp.Branch == cmbBranch.SelectedValue && 
               emp.Dept == cmbDept.SelectedValue && 
               emp.ID == empId
        select new
        {
            emp.Emp_name,
            emp.ID,
            emp.Designation,
            emp.Dept,
            emp.Branch,
            exc.Action_date
        };
}