How to call Eval by column index? [Answered]RSS

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  lucky7456969

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  How to call Eval by column index?

  Apr 22, 2015 06:07 AM|lucky7456969|LINK

  Hello,

  My resultset comes from a dynamic query, so that the column names are not known in advance.

  When binding those up with the GridView, I can't call Eval by name, how do I call them by column index?

  Thanks

  Jack

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  Ashim Chatte...

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  Re: How to call Eval by column index?

  Apr 22, 2015 08:04 AM|Ashim Chatterjee|LINK

  lucky7456969

  , how do I call them by column index?

  You can't.You can use DataItem here for explicit casting see https://support2.microsoft.com/default.aspx?scid=kb;en-us;307860.

  Perplexity is the beginning of knowledge.
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  Fei Han - MS...

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  Re: How to call Eval by column index?

  Apr 23, 2015 01:09 AM|Fei Han - MSFT|LINK

  Hi Jack,

  Thanks for your post.

  lucky7456969

  My resultset comes from a dynamic query, so that the column names are not known in advance.

  GridView could automatically generate columns if AutoGenerateColumns property is set to true. You could try to let your GridView automatically generate columns, this sample is for your reference.

  <div>
      <asp:Button ID="btnsource1" runat="server" Text="BindWithSource1" OnClick="btnsource1_Click" /><asp:Button ID="btnsource2" runat="server" Text="BindWithSource2" OnClick="btnsource2_Click" />
      <asp:GridView ID="GridView1" runat="server"></asp:GridView>
  </div> 
  

  protected void btnsource1_Click(object sender, EventArgs e)
  {
      BindWithSource1();
  }
  
  private void BindWithSource1()
  {
      DataTable dt = new DataTable();
      dt.Columns.Add("ID");
      dt.Columns.Add("Name");
      dt.Columns.Add("Age");
  
      dt.Rows.Add(1, "Tom", 28);
      dt.Rows.Add(2, "Jerry", 25);
      dt.Rows.Add(3, "Simmons", 30);
  
      GridView1.DataSource = dt;
      GridView1.DataBind();
  }
  
  protected void btnsource2_Click(object sender, EventArgs e)
  {
      BindWithSource2();
  }
  
  private void BindWithSource2()
  {
      DataTable dt = new DataTable();
      dt.Columns.Add("ID");
      dt.Columns.Add("Price");
      dt.Columns.Add("Num");
      dt.Columns.Add("Total");
  
      dt.Rows.Add(1, 15, 20,300);
      dt.Rows.Add(2, 100, 2, 200);
  
      GridView1.DataSource = dt;
      GridView1.DataBind();
  } 
  

  

  Best Regards,

  Fei Han

  
  
  

  
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