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GeneralRe: Copy a selected gridview row to the same gridview Pin
Nathan Minier24-Mar-21 1:20
professionalNathan Minier24-Mar-21 1:20 
GeneralRe: Copy a selected gridview row to the same gridview Pin
jsc4224-Mar-21 1:25
professionaljsc4224-Mar-21 1:25 
GeneralRe: Copy a selected gridview row to the same gridview Pin
Nathan Minier24-Mar-21 1:38
professionalNathan Minier24-Mar-21 1:38 
GeneralRe: Copy a selected gridview row to the same gridview Pin
jsc4225-Mar-21 3:54
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QuestionHow to able to have the information of the particular image button clicked? Pin
Member 1508474922-Mar-21 10:50
MemberMember 1508474922-Mar-21 10:50 
AnswerRe: How to able to have the information of the particular image button clicked? Pin
OriginalGriff22-Mar-21 11:18
mveOriginalGriff22-Mar-21 11:18 
GeneralRe: How to able to have the information of the particular image button clicked? Pin
Richard Deeming22-Mar-21 22:25
mveRichard Deeming22-Mar-21 22:25 
AnswerRe: How to able to have the information of the particular image button clicked? Pin
Richard Deeming22-Mar-21 22:33
mveRichard Deeming22-Mar-21 22:33 
Member 15084749 wrote:
String SQL = "Select * from Book_List where Book_category='" + Label1.Text + "'";
Don't do it like that!

Although this specific case is OK since you're using a constant value, using string concatenation to build a SQL query can and will leave you vulnerable to SQL Injection[^].

NEVER use string concatenation to build a SQL query. ALWAYS use a parameterized query.
const string SQL = "Select * from Book_List where Book_category = @BookCategory";
SqlDataAdapter da = new SqlDataAdapter(SQL, con);
da.SelectCommand.Parameters.AddWithValue("@BookCategory", Label1.Text);
Everything you wanted to know about SQL injection (but were afraid to ask) | Troy Hunt[^]
How can I explain SQL injection without technical jargon? | Information Security Stack Exchange[^]
Query Parameterization Cheat Sheet | OWASP[^]

Also, don't store the database connection in a class-level field. Instead, create it where necessary, and wrap it in a using block to ensure that it's always disposed of properly.
private static SqlConnection CreateConnection()
{
    return new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);
}

...

DataSet ds = new DataSet();
using (SqlConnection con = CreateConnection())
{
    const string SQL = "Select * from Book_List where Book_category = @BookCategory";
    SqlDataAdapter da = new SqlDataAdapter(SQL, con);
    da.SelectCommand.Parameters.AddWithValue("@BookCategory", Label1.Text);
    da.Fill(ds);
}

DataTable dt = ds.Tables[0];
...

And do yourself a favour and give your controls meaningful IDs, rather than accepting the default values suggested by the Visual Studio designer. Sure, you might remember what Label1 refers to now, but when you come back to your code in three weeks, you'll have forgotten.

As to your question, Page_Load is too late to initialize your dynamic controls. Do it in Page_Init instead.



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- Homer

AnswerRe: How to able to have the information of the particular image button clicked? Pin
DerekT-P23-Mar-21 0:46
professionalDerekT-P23-Mar-21 0:46 
QuestionC# Excel test specific cells in a column Pin
Steve Rudd22-Mar-21 5:59
MemberSteve Rudd22-Mar-21 5:59 
AnswerRe: C# Excel test specific cells in a column Pin
Gerry Schmitz22-Mar-21 7:40
mveGerry Schmitz22-Mar-21 7:40 
GeneralRe: C# Excel test specific cells in a column Pin
Steve Rudd22-Mar-21 9:31
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GeneralRe: C# Excel test specific cells in a column Pin
Richard MacCutchan22-Mar-21 22:56
mveRichard MacCutchan22-Mar-21 22:56 
GeneralRe: C# Excel test specific cells in a column Pin
Steve Rudd23-Mar-21 0:13
MemberSteve Rudd23-Mar-21 0:13 
GeneralRe: C# Excel test specific cells in a column Pin
Steve Rudd23-Mar-21 1:32
MemberSteve Rudd23-Mar-21 1:32 
GeneralRe: C# Excel test specific cells in a column Pin
Richard MacCutchan23-Mar-21 2:09
mveRichard MacCutchan23-Mar-21 2:09 
QuestionMike`s Gradiator Pin
Alejandro01122-Mar-21 2:22
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AnswerRe: Mike`s Gradiator Pin
Richard Deeming22-Mar-21 2:41
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GeneralRe: Mike`s Gradiator Pin
Alejandro01122-Mar-21 2:48
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AnswerRe: Mike`s Gradiator Pin
Gerry Schmitz22-Mar-21 7:49
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GeneralRe: Mike`s Gradiator Pin
Alejandro01122-Mar-21 10:16
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GeneralRe: Mike`s Gradiator Pin
Alejandro01123-Mar-21 14:53
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QuestionHow to write to Form1.texBox1 from another class. Pin
Member 1406872419-Mar-21 11:17
MemberMember 1406872419-Mar-21 11:17 
AnswerRe: How to write to Form1.texBox1 from another class. Pin
OriginalGriff19-Mar-21 12:24
mveOriginalGriff19-Mar-21 12:24 
QuestionCombobox Text Pin
Ismael Oliveira 202119-Mar-21 8:01
MemberIsmael Oliveira 202119-Mar-21 8:01 

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