Member Avatar for neel_patric

im trying to compare a value that a user can input in a txt box to a record in a database.

for example i have a txt box which has id as txtStudId. now i have a db which has already been linked to the form using the access data source control.

in the database, there exists a student table, where the Stud_ID field contains student id's against which i have to compare.

so when i enter say s112233 in the txt box nd click on a button, say btnLogin, how do i compare this with Stud_ID in the student table?
im lost.....any help will be appreciated.

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  • Latest Post Latest Post by kvprajapati

Dani AI

Generated

: since you are on ASP.NET Web Forms with an Access DB, the cleanest Web-Forms approach is to bind an AccessDataSource SelectCommand to a ControlParameter (no string concatenation in code). correctly pointed out the general SQL approach, but using the AccessDataSource avoids manual connection/command plumbing and keeps the parameterization automatic and safer.

Example AccessDataSource markup (put this on the page and point DataFile or ConnectionString to your .mdb/.accdb):

<asp:AccessDataSource ID="adsStudents" runat="server"
    DataFile="~/App_Data/Students.mdb"
    SelectCommand="SELECT Stud_ID FROM Student WHERE Stud_ID = ?">
    <SelectParameters>
        <asp:ControlParameter ControlID="txtStudId" PropertyName="Text" Type="String" />
    </SelectParameters>
</asp:AccessDataSource>

Then, in your VB code-behind (for the button click), call the control's Select and check the returned DataView for matches:

Dim dv As DataView = CType(adsStudents.Select(DataSourceSelectArguments.Empty), DataView)
If dv.Count > 0 Then
    ' student id exists — proceed
Else
    ' no match — handle accordingly
End If

Notes and troubleshooting:

  • Always trim/validate txtStudId.Text (use a RegularExpressionValidator for the expected pattern like "s" + digits). Do server-side validation too.
  • Parameterized AccessDataSource avoids SQL injection that happens when concatenating strings.
  • Access can be case-insensitive; if you need exact casing compare or normalization, normalize both sides (Trim/UCase) before checking.
  • Ensure the ASP.NET process can read/write the Access file (App_Data permissions) and be aware Access is not ideal for high-concurrency sites — consider SQL Server or MySQL if you need to scale.

Recommended Answers

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Member Avatar for kvprajapati 
....
qry=select * from tablename where col1='" + text1.text + "' and col2='" + text2.text + "'";
....
Member Avatar for neel_patric

im sorry im not familiar with c# syntax. i see there r some sql statements aswel. im not familiar with this too. im using visual web develper and using an access database with access data source control

Member Avatar for kvprajapati

Which language you own?

Member Avatar for kvprajapati

I presume that your project uses MS-SQL Server Database.

Sub Button1_Click(....) 
        Dim cn as new System.Data.SqlClient.SqlConnection("your connection string")
        Dim qry as String
        qry="select username from login where username='" & TextBox1.Text & "' and password='" & TextBox2.Text & "'"

        Dim cmd as new System.Data.SqlClient.SqlCommand(qry,Cn)
        Dim oRet as Object
        cn.Open()
        oRet=cmd.ExecuteScalar()
        cn.Close()

         if ISDBNull(oRet) then
               .... No - Match
          else
              ... Match
          End if
     .....
     ....
   End Sub
Member Avatar for neel_patric

using access database and not sql....

thanks....

Member Avatar for neel_patric

do u know how u kud do it with access database?

Member Avatar for kvprajapati

Code snippet to use access db.

Sub Button1_Click(....) 
        Dim cn as new System.Data.OleDb.OledbConnection("your connection string")
        Dim qry as String
        qry="select username from login where username='" & TextBox1.Text & "' and password='" & TextBox2.Text & "'"

        Dim cmd as new System.Data.OleDb.OledbCommand(qry,Cn)
        Dim oRet as Object
        cn.Open()
        oRet=cmd.ExecuteScalar()
        cn.Close()

         if ISDBNull(oRet) then
               .... No - Match
          else
              ... Match
          End if
     .....
     ....
   End Sub
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