set value of custom control textbox on button click event

Question

User76727224 posted

I am creating custom web control(textbox) which allows only integer data type in textbox. On button(simple asp button) submit event if there is no data in textbox, custom control should set TextBox1.Text=0, this is what i want. This is code which i wrote.

I checked few events or methods for this but they got fired after btnA_click event. I am kind of newbie in this. Any event or method i am missing? Any suggestion accepted. Thanks in Advance...

public class MasIntTextBox : TextBox
{
    private RequiredFieldValidator req;
    private RegularExpressionValidator regex;
    public string ValGrp { get; set; }
    public string IsRequired { get; set; }

    protected override void OnInit(EventArgs e)
    {
        //this.CssClass = "inp-form";
        if (IsRequired == "true" || IsRequired == "yes")
        {
            req = new RequiredFieldValidator();
            req.ControlToValidate = this.ID;
            req.ErrorMessage = "Enter Numeric Value";
            req.Display = ValidatorDisplay.Dynamic;
            if (!string.IsNullOrEmpty(ValGrp))
                req.ValidationGroup = ValGrp;
            Controls.Add(req);
        }
        regex = new RegularExpressionValidator();
        regex.ControlToValidate = this.ID;
        regex.ErrorMessage = "Numeric Value Only";
        regex.Display = ValidatorDisplay.Dynamic;
        regex.ValidationExpression = "^\\d+(\\.\\d+)?$";
        if (!string.IsNullOrEmpty(ValGrp))
            regex.ValidationGroup = ValGrp;
        Controls.Add(regex);
        //base.OnInit(e);
    }

    protected override void Render(HtmlTextWriter w)
    {
        base.Render(w);
        if (IsRequired == "true" || IsRequired == "yes")
            req.RenderControl(w);
        regex.RenderControl(w);
    }
}

I want to write code in this class for this requirement.

Thanks in advanced...

Answer 1

User713354600 posted

use simple javascript, onclick event set you textbox value to 0 if the textbox is empty

Answer 2

User76727224 posted

thnx for reply but as i said, i want to write this code in custom control itself.

Answer 3

User3866881 posted

thnx for reply but as i said, i want to write this code in custom control itself.

Hi,

When you want to dynamically create a web-side control, please just put it directly in the ChildControlCreate method and do something like this following：

1）You should use ViewState to contain value in order to avoid html's losing value when rendering。

2）Please put the dynamically creating controls in the CreateChildControls……

public class MasIntTextBox : WebControl
    {
        private TextBox txt = null;
        private RequiredFieldValidator req;
        private RegularExpressionValidator regex;
        public string ValGrp
        {
            get
            {
                return ViewState["grp"] == null ? string.Empty : ViewState["grp"].ToString();
            }
            set
            {
                ViewState["grp"] = value;
            }
        }
        public string IsRequired
        {
            get
            {
                return ViewState["required"] == null ? "yes" : ViewState["required"].ToString();
            }
            set
            {
                 ViewState["required"] = value;
            }
        }
 
        protected override void CreateChildControls()
        {
            txt = new TextBox();
            txt.ID = "mytxt";
            Controls.Add(txt);
            if (IsRequired == "true" || IsRequired == "yes")
            {
                req = new RequiredFieldValidator();
                req.ControlToValidate = txt.ID;
                req.ErrorMessage = "Enter Numeric Value";
                req.Display = ValidatorDisplay.Dynamic;
                if (!string.IsNullOrEmpty(ValGrp))
                    req.ValidationGroup = ValGrp;
                Controls.Add(req);
            }
            regex = new RegularExpressionValidator();
            regex.ControlToValidate = txt.ID;
            regex.ErrorMessage = "Numeric Value Only";
            regex.Display = ValidatorDisplay.Dynamic;
            regex.ValidationExpression = "^\\d+(\\.\\d+)?$";
            if (!string.IsNullOrEmpty(ValGrp))
                regex.ValidationGroup = ValGrp;
            Controls.Add(regex);
        }
        protected override void Render(HtmlTextWriter w)
        {
            txt.RenderControl(w);
            if (IsRequired == "true" || IsRequired == "yes")
                req.RenderControl(w);
            regex.RenderControl(w);
        }
    }

Answer 4

User76727224 posted

I guess i was not clear, I want something like this. There are some textbox of custom web control (textbox) which allows only integer values to enter.. Now when i click submit, if that textbox is empty then it should set the value to 0 so i dont have to check every time that if there is value or blank and i dont have to andle error...

Answer 5

User3866881 posted

I guess i was not clear, I want something like this. There are some textbox of custom web control (textbox) which allows only integer values to enter.. Now when i click submit, if that textbox is empty then it should set the value to 0 so i dont have to check every time that if there is value or blank and i dont have to andle error...

Hi，

I think you can just assign the value of "0" to the TextBox in the  CreateChildControls.

Reguards！

Answer 6

User76727224 posted

Hi,

thnx for reply.

adding it in childcontrol creating event, the value and properties of that textbox i can't access...why..? i am trying but somehow its small mistake...

Regards..

Answer 7

User3866881 posted

adding it in childcontrol creating event, the value and properties of that textbox i can't access...why..? i am trying but somehow its small mistake...

What does that mean？