跳过如果else语句有一个错误检查 [英] Skipped one error checking in if else statement
问题描述
我必须使用的if else说明书在我的计划这个错误检查。我有两件事情要检查。他们是
I have this error checking in my program using the if else statment. I got 2 things to check. They are
-
PoliceID（PK）
PoliceID(PK)
身份证号码
下面检查语句如果文本框有PoliceID和身份证在数据库相同的值。
The statement below checks if the textbox has the same value for PoliceID and NRIC as in the database.
if (tbpid.Text.Equals(dr["policeid"].ToString().Trim()) && (tbnric.Text.Equals(dr["nric"].ToString().Trim())))
{
lbmsg.Text = "This police account has already exist. Please verify the details again.";
}
如果文本框（警察id）的具有相同的值作为在数据库中，它们将给出另一个不同的错误。
If the textbox (police id) has the same value as in the database, they will give another different error.
if (tbpid.Text.Equals(dr["policeid"].ToString()))
{
lbmsg.Text = "This police ID has already exists. Please generate another Police ID";
}
如果文本框（身份证）具有相同的值在数据库中，它们将给出另一个错误
If the textbox (NRIC) has the same value as in the database, they will give another error
if (tbnric.Text.Equals(dr["nric"].ToString()))
{
lbmsg.Text ="This NRIC has already exist. Please ensure that the NRIC is correct";
}
如果我是所有错误校验信息结合在一起将是这个样子。
and if i were to combine all error checking message together it will be like this.
protected void btnAdd_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection("Data Source = localhost; Initial Catalog = MajorProject; Integrated Security= SSPI");
con.Open();
SqlCommand select = new SqlCommand("Select policeid, nric from PoliceAccount where policeid = @policeid" , con);
SqlDataReader dr;
select.Parameters.AddWithValue("@policeid", tbpid.Text);
dr = select.ExecuteReader();
if(dr.Read())
{
if (tbpid.Text.Equals(dr["policeid"].ToString().Trim()) && (tbnric.Text.Equals(dr["nric"].ToString().Trim())))
{
lbmsg.Text = "This police account has already exist. Please verify the details again.";
}
else if (tbpid.Text.Equals(dr["policeid"].ToString()))
{
lbmsg.Text = "This police ID has already exists. Please generate another Police ID";
}
else if (tbnric.Text.Equals(dr["nric"].ToString()))
{
lbmsg.Text ="This NRIC has already exist. Please ensure that the NRIC is correct";
}
}
else
{
SqlConnection conn = new SqlConnection("Data Source = localhost; Initial Catalog = MajorProject; Integrated Security= SSPI");
conn.Open();
SqlCommand cmd = new SqlCommand("insert into PoliceAccount(policeid, password, nric, fullname, postedto) values('" + tbpid.Text.Trim() + "','" + tbpid.Text.Trim() + "','" + tbnric.Text.Trim() + "','" + tbfullname.Text.Trim() + "', '" + ddllocation.SelectedValue + "')", conn);
cmd.ExecuteNonQuery();
conn.Close();
lbmsg.Text = "Congratulations. The police account of ID " + tbpid.Text + " has been successfully added. You may edit the profile via the edit profile tab above";
tbpid.Text = "";
tbnric.Text = "";
tbfullname.Text = "";
ddllocation.SelectedValue = "Select Location";
}
//ConfirmButtonExtender2.ConfirmText = "Are you sure you want to add this Police Account " + tbpid.Text + " ?";
}
}
然而这里的问题是，该错误检查信息的头两个语句管理工作。不幸的是，身份证一个没工作。例如，如果我是键入一个不同的policeID但相同的身份证，数据仍然插入，这意味着它完全忽略上面的身份证号码错误校验数据库。我一直在寻找这几个小时，我还没有发现问题。将AP preciate如果任何人都可以指导我在此。
However the problem here is, the first two statement of the error checking message managed to work. Unfortunately, the NRIC one did not work. For example, if i were to type a different policeID but the same NRIC, the data is still being inserted into the database which means it totally ignore the NRIC error check above. I have been looking at it for hours and i have yet to find the problem. Would appreciate if anyone can guide me on this.
要添加的，在我的数据库，我已经把我的主键作为 policeID ，而身份证号码只是一个常规数据列在我的数据库
To add on, in my database, i have set my primary key as the policeID while NRIC is just a regular data column in my database
问候。
推荐答案
由于此查询的最后一个没有工作
The Last one didn't work because of this query
选择policeid，从PoliceAccount身份证，其中policeid = @ policeid
因为ploiceid不存在这样的手段不会返回任何行 dr.Read（）是假的，因为没有行字，所以它会直接在其他部分，你要插入在数据库中的数据。因此，要使它发挥作用。尝试像这样...
Select policeid, nric from PoliceAccount where policeid=@policeid
This will not return any row since ploiceid doesn't exist means dr.Read() is false since no rows to read , so it goes directly in else part where you are inserting data in database . So to make it work. try like this...
if(dr.Read())
{
if (tbpid.Text.Equals(dr["policeid"].ToString().Trim()) && (tbnric.Text.Equals(dr["nric"].ToString().Trim())))
{
lbmsg.Text = "This police account has already exist. Please verify the details again.";
}
else if (tbpid.Text.Equals(dr["policeid"].ToString()))
{
lbmsg.Text = "This police ID has already exists. Please generate another Police ID";
}
}
else
{
if (tbnric.Text.Equals(dr["nric"].ToString()))
{
lbmsg.Text ="This NRIC has already exist. Please ensure that the NRIC is correct";
}
else
{
SqlConnection conn = new SqlConnection("Data Source = localhost; Initial Catalog = MajorProject; Integrated Security= SSPI");
conn.Open();
SqlCommand cmd = new SqlCommand("insert into PoliceAccount(policeid, password, nric, fullname, postedto) values('" + tbpid.Text.Trim() + "','" + tbpid.Text.Trim() + "','" + tbnric.Text.Trim() + "','" + tbfullname.Text.Trim() + "', '" + ddllocation.SelectedValue + "')", conn);
cmd.ExecuteNonQuery();
conn.Close();
lbmsg.Text = "Congratulations. The police account of ID " + tbpid.Text + " has been successfully added. You may edit the profile via the edit profile tab above";
tbpid.Text = "";
tbnric.Text = "";
tbfullname.Text = "";
ddllocation.SelectedValue = "Select Location";
}
}
为了使现有的code的工作尝试此查询
To make your Existing code work try this query
选择policeid，从PoliceAccount身份证，其中policeid = @ policeid或身份证= @身份证
它总是会返回行，如果在数据库中存在的一个ID，如果两人都没有比它插入到数据库中。
It will always return rows if one of the id exist in database if both didn't than it insert in to database.
这篇关于跳过如果else语句有一个错误检查的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
