c# Sqlcommand error
foreach (string str in TestWords)
{
//spam
SqlCommand cmd6 = new SqlCommand("select count from keys,files,folders where keys.fileid=files.id and keys.kname='" + str + "' and files.spam=1 and folders.id<>" + FolIter + " and files.folderid<>" + FolIter + " and files.id='" + s[0].ToString + "'", cn);
int i6 = Convert.ToInt16(cmd6.ExecuteScalar());
double temp = Convert.ToDouble((i6 + 1) / (i7 + i8));
//non spam
**error**
SqlCommand cmd9 = new SqlCommand("select count from keys,files,folders where keys.fileid=files.id and keys.kname='"
+ str
+ "' and files.spam=0 and folders.id<>"
+ FolIter
+ " and files.folderid<>"
+ FolIter
+ " and files.id='"
+ s[0].ToString
+ "'", cn);
int i9 = Convert.ToInt16(cmd9.ExecuteScalar());
temp2 = Convert.ToDouble((i9 + 1) / (i7 + i8));
Sdoc = Convert.T开发者_运维技巧oDouble(Sdoc * temp);
NsDoc = Convert.ToDouble(NsDoc * temp2);
}
The error iam getting is:Operator '+' cannot be applied to operands of type 'string' and 'method group'
You have to call the method:
s[0].ToString()
As Nix, Femaref and Azhar mentioned, .ToString() is the typo that triggers the error message.
May I suggest to use parameters instead of string concatenation ? This way:
SqlCommand cmd9 = new SqlCommand("select count from keys,files,folders where keys.fileid=files.id and keys.kname=@name and and files.spam=0 and folders.id<>@FolIter and files.folderid<>@FolIter and files.id=@s0", cn);
cmd9.Parameters.Add(new SqlParameter("@name", str));
cmd9.Parameters.Add(new SqlParameter("@FolIter", FolIter));
cmd9.Parameters.Add(new SqlParameter("s0", s0));
By this way, ADO.NET will deal with your variable as is, you wont have to convert them to string to use concatenation, and you wont be exposed to a SQL injection risk.
You are using method ToString()
as Property
change s[0].ToString
-> s[0].ToString()
Remember C# does not allow it.
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