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Christian H #1
dynamically add controls and validators - always false
Based on the content in my database, I need to populate different form
controls and validators, such as textbox, dropdownlist,
requiredfieldvalidators , etc.
Then I need to check if the form has been filled out correctly. If so, I
need to update a database, and do other things.
In order to check if the form is ok, I've tried looping through the
validator controls, and I've also tried using page.isvalid.
Nomatter what, the form seems to be incorrrectly filled out. The validator
controls comes out as "false", and Page.isvalid also comes out as false.
Regards C.H
Here is a modified example of my problem, so that you can see what I'm
dealing with.
<%@ Page language="c#" Codebehind="testfil1.aspx.cs" AutoEventWireup="false"
Inherits="smbuClass.testfil1" Trace=true enableViewState=false %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
<HEAD>
<title>testfil1</title>
<meta name="GENERATOR" Content="Microsoft Visual Studio 7.0">
<meta name="CODE_LANGUAGE" Content="C#">
<meta name="vs_defaultClientScript" content="JavaScript">
<meta name="vs_targetSchema"
content="http://schemas.microsoft.com/intellisense/ie5">
</HEAD>
<body MS_POSITIONING="GridLayout">
<form runat="server" ID="Form1" method="post" action="testfil1.aspx">
<asp:placeholder id="plh" runat="server" />
<asp:button Text="Click" runat="server" CausesValidation="true"
ID="Button" />
</form>
</body>
</HTML>
using System;
using System.Data;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Collections;
namespace smbuClass
{
public class testfil1 : System.Web.UI.Page
{
protected RequiredFieldValidator validator2 = new
RequiredFieldValidator();
protected TextBox txtfield=new TextBox();
protected System.Web.UI.WebControls.Button Button;
protected PlaceHolder plh;
private void Page_Load(Object sender,EventArgs e)
{
txtfield.ID="txtfield";
plh.Controls.Add(txtfield);
validator2.ControlToValidate=txtfield.ID+"";
validator2.ID="validator2";
validator2.Text = "Error";
validator2.ErrorMessage="Error";
validator2.EnableClientScript=false;
plh.Controls.Add(validator2);
if(Page.IsPostBack)
{
Page.Validate();
if(Page.IsValid)
Response.Write("all ok");
else
Response.Write("not ok");
foreach(BaseValidator b in Page.Validators)
{
Trace.Warn(b.IsValid + " " +b.ID + " ");
}
}
}
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}
private void InitializeComponent()
{
this.Load += new System.EventHandler(this.Page_Load);
}
}
}
Christian H Guest
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Teemu Keiski #2 Re: dynamically add controls and validators - always false
I go track of the error now.
Change the code like this:
protected override void CreateChildControls()
{
RequiredFieldValidator validator2 = new RequiredFieldValidator();
TextBox txtfield=new TextBox();
txtfield.ID="txtfield";
plh.Controls.Add(txtfield);
plh.Controls.Add(validator2);
validator2.ControlToValidate=txtfield.ID;
validator2.ID="validator2";
validator2.Text = "Error";
validator2.ErrorMessage="Error";
validator2.EnableClientScript=false;
}
Just add this overridden CreateChildControls to the Page and remove the
relevant code from Page_Load. That should do it. (Page.Validate etc can
still be where they are now)
--
Teemu Keiski
MCP, Designer/Developer
Mansoft tietotekniikka Oy
[url]http://www.mansoft.fi[/url]
AspInsiders Member, [url]www.aspinsiders.com[/url]
ASP.NET Forums Moderator, [url]www.asp.net[/url]
AspAlliance Columnist, [url]www.aspalliance.com[/url]
"Christian H" <no@name.no> wrote in message
news:uDPTYxOUDHA.2420@TK2MSFTNGP10.phx.gbl...AutoEventWireup="false"> Based on the content in my database, I need to populate different form
> controls and validators, such as textbox, dropdownlist,
> requiredfieldvalidators , etc.
>
> Then I need to check if the form has been filled out correctly. If so, I
> need to update a database, and do other things.
>
> In order to check if the form is ok, I've tried looping through the
> validator controls, and I've also tried using page.isvalid.
>
> Nomatter what, the form seems to be incorrrectly filled out. The validator
> controls comes out as "false", and Page.isvalid also comes out as false.
>
>
> Regards C.H
>
>
>
>
> Here is a modified example of my problem, so that you can see what I'm
> dealing with.
>
> <%@ Page language="c#" Codebehind="testfil1.aspx.cs"> Inherits="smbuClass.testfil1" Trace=true enableViewState=false %>
> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
> <HTML>
> <HEAD>
> <title>testfil1</title>
> <meta name="GENERATOR" Content="Microsoft Visual Studio 7.0">
> <meta name="CODE_LANGUAGE" Content="C#">
> <meta name="vs_defaultClientScript" content="JavaScript">
> <meta name="vs_targetSchema"
> content="http://schemas.microsoft.com/intellisense/ie5">
> </HEAD>
> <body MS_POSITIONING="GridLayout">
> <form runat="server" ID="Form1" method="post" action="testfil1.aspx">
> <asp:placeholder id="plh" runat="server" />
> <asp:button Text="Click" runat="server" CausesValidation="true"
> ID="Button" />
> </form>
> </body>
> </HTML>
>
> using System;
> using System.Data;
> using System.Web.UI;
> using System.Web.UI.WebControls;
> using System.Collections;
>
> namespace smbuClass
> {
> public class testfil1 : System.Web.UI.Page
> {
>
> protected RequiredFieldValidator validator2 = new
> RequiredFieldValidator();
> protected TextBox txtfield=new TextBox();
> protected System.Web.UI.WebControls.Button Button;
> protected PlaceHolder plh;
>
> private void Page_Load(Object sender,EventArgs e)
> {
>
> txtfield.ID="txtfield";
> plh.Controls.Add(txtfield);
>
> validator2.ControlToValidate=txtfield.ID+"";
> validator2.ID="validator2";
> validator2.Text = "Error";
> validator2.ErrorMessage="Error";
> validator2.EnableClientScript=false;
> plh.Controls.Add(validator2);
>
>
> if(Page.IsPostBack)
> {
> Page.Validate();
> if(Page.IsValid)
> Response.Write("all ok");
> else
> Response.Write("not ok");
>
> foreach(BaseValidator b in Page.Validators)
> {
> Trace.Warn(b.IsValid + " " +b.ID + " ");
> }
>
> }
>
>
>
>
>
> }
>
>
> override protected void OnInit(EventArgs e)
> {
> //
> // CODEGEN: This call is required by the ASP.NET Web Form Designer.
> //
> InitializeComponent();
> base.OnInit(e);
> }
>
> private void InitializeComponent()
> {
> this.Load += new System.EventHandler(this.Page_Load);
>
> }
>
> }
> }
>
>
>
>
Teemu Keiski Guest
-
Teemu Keiski #3 Re: dynamically add controls and validators - always false
Answered this on aspnet group and ASP.NET Forums.
I got track of the error now.
Change the code like this:
protected override void CreateChildControls()
{
RequiredFieldValidator validator2 = new RequiredFieldValidator();
TextBox txtfield=new TextBox();
txtfield.ID="txtfield";
plh.Controls.Add(txtfield);
plh.Controls.Add(validator2);
validator2.ControlToValidate=txtfield.ID;
validator2.ID="validator2";
validator2.Text = "Error";
validator2.ErrorMessage="Error";
validator2.EnableClientScript=false;
}
Just add this overridden CreateChildControls to the Page and remove the
relevant code from Page_Load. That should do it. (Page.Validate etc can
still be where they are now)
--
Teemu Keiski
MCP, Designer/Developer
Mansoft tietotekniikka Oy
[url]http://www.mansoft.fi[/url]
AspInsiders Member, [url]www.aspinsiders.com[/url]
ASP.NET Forums Moderator, [url]www.asp.net[/url]
AspAlliance Columnist, [url]www.aspalliance.com[/url]
"Christian H" <no@name.no> wrote in message
news:OhA40wOUDHA.2200@TK2MSFTNGP11.phx.gbl...AutoEventWireup="false"> Based on the content in my database, I need to populate different form
> controls and validators, such as textbox, dropdownlist,
> requiredfieldvalidators , etc.
>
> Then I need to check if the form has been filled out correctly. If so, I
> need to update a database, and do other things.
>
> In order to check if the form is ok, I've tried looping through the
> validator controls, and I've also tried using page.isvalid.
>
> Nomatter what, the form seems to be incorrrectly filled out. The validator
> controls comes out as "false", and Page.isvalid also comes out as false.
>
> I'm not sure what I need to do in order to make this work. Do I need to
> create my own custom control?
>
> Regards C.H
>
>
>
>
> Here is a modified example of my problem, so that you can see what I'm
> dealing with.
>
> <%@ Page language="c#" Codebehind="testfil1.aspx.cs"> Inherits="smbuClass.testfil1" Trace=true enableViewState=false %>
> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
> <HTML>
> <HEAD>
> <title>testfil1</title>
> <meta name="GENERATOR" Content="Microsoft Visual Studio 7.0">
> <meta name="CODE_LANGUAGE" Content="C#">
> <meta name="vs_defaultClientScript" content="JavaScript">
> <meta name="vs_targetSchema"
> content="http://schemas.microsoft.com/intellisense/ie5">
> </HEAD>
> <body MS_POSITIONING="GridLayout">
> <form runat="server" ID="Form1" method="post" action="testfil1.aspx">
> <asp:placeholder id="plh" runat="server" />
> <asp:button Text="Click" runat="server" CausesValidation="true"
> ID="Button" />
> </form>
> </body>
> </HTML>
>
>
> using System;
> using System.Data;
> using System.Web.UI;
> using System.Web.UI.WebControls;
> using System.Collections;
>
> namespace smbuClass
> {
> public class testfil1 : System.Web.UI.Page
> {
>
> protected RequiredFieldValidator validator2 = new
> RequiredFieldValidator();
> protected TextBox txtfield=new TextBox();
> protected System.Web.UI.WebControls.Button Button;
> protected PlaceHolder plh;
>
> private void Page_Load(Object sender,EventArgs e)
> {
>
> txtfield.ID="txtfield";
> plh.Controls.Add(txtfield);
>
> validator2.ControlToValidate=txtfield.ID+"";
> validator2.ID="validator2";
> validator2.Text = "Error";
> validator2.ErrorMessage="Error";
> validator2.EnableClientScript=false;
> plh.Controls.Add(validator2);
>
>
> if(Page.IsPostBack)
> {
> Page.Validate();
> if(Page.IsValid)
> Response.Write("all ok");
> else
> Response.Write("not ok");
>
> foreach(BaseValidator b in Page.Validators)
> {
> Trace.Warn(b.IsValid + " " +b.ID + " ");
> }
>
> }
>
>
>
>
>
> }
>
>
> override protected void OnInit(EventArgs e)
> {
> //
> // CODEGEN: This call is required by the ASP.NET Web Form Designer.
> //
> InitializeComponent();
> base.OnInit(e);
> }
>
> private void InitializeComponent()
> {
> this.Load += new System.EventHandler(this.Page_Load);
>
> }
>
> }
> }
>
>
>
>
>
Teemu Keiski Guest
-
Christian H #4 thank you! - where can I learn more?
Thank you!
I need some advice on what to read in order to learn more about these
things.
Why did I need to override that method, and how will I know when I will need
to override a method next time...?
I've got a feeling I'm going to need to override methods a lot with this
project
Do you have an book suggestion, or online tutorials that will educate me on
this?
Regards Christian H.
Christian H Guest
-
Teemu Keiski #5 Re: thank you! - where can I learn more?
The CreateChildControls overriding was just because Page inherits from
System.Web.UI.Control that again uses CreateChildControls to ensure child
controls are created in proper place and at proper time. Basically if you'd
add those controls in Page_Init that would have done it as well.
If you want book recommendation get "Developing ASP.NET Server Controls and
Components" by MSPress.
--
Teemu Keiski
MCP, Designer/Developer
Mansoft tietotekniikka Oy
[url]http://www.mansoft.fi[/url]
AspInsiders Member, [url]www.aspinsiders.com[/url]
ASP.NET Forums Moderator, [url]www.asp.net[/url]
AspAlliance Columnist, [url]www.aspalliance.com[/url]
"Christian H" <no@name.no> wrote in message
news:O75eQyPUDHA.2420@TK2MSFTNGP10.phx.gbl...need> Thank you!
>
> I need some advice on what to read in order to learn more about these
> things.
> Why did I need to override that method, and how will I know when I willon> to override a method next time...?
>
> I've got a feeling I'm going to need to override methods a lot with this
> project
> Do you have an book suggestion, or online tutorials that will educate me> this?
>
> Regards Christian H.
>
>
>
Teemu Keiski Guest
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