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In my Windows Application, there is a form called Order Details in which I used many textboxes and comboboxes to input data. Whenever the user will click the Add button it should prompt the user if there will be a blank textbox if the user left it blank. How is it possible?
I dont know more. Please help me.
Posted
Comments
thatraja 12-Oct-13 2:29am
   
Google for "C# Validate empty textboxes"

you should use if else statemet for this

C#
if(textbox1.text!="" && textbox2.text!="" or so no...)
{
your code.....
}
else
{
message.show("Please fill full info ");

}
   
v2
Try in this way;

private bool WithErrors()
{
    if(textBox1.Text.Trim() == String.Empty) 
        return true; // Returns true if no input or only space is found
    if(textBox2.Text.Trim() == String.Empty)
        return true;
    // Other textBoxes.

    return false;
}

private void buttonSubmit_Click(object sender, EventArgs e)
{
    if(WithErrors())
    {
        // Notify user for error.
    }
    else
    {
        // Do whatever here... Submit
    }
}
   
I'm assuming you don't wanna check the textboxes individually, like

C#
//C# 4.0
if (String.IsNullOrWhiteSpace(textbox.Text)) 
{
//The textbox is empty.
MessageBox.Show("You have empty fields in the form");
}

//C# < 4.0
if (String.IsNullOrEmpty(textbox.Text.Trim())
{
//The textbox is empty.
MessageBox.Show("You have empty fields in the form");
}


That allows you to check a specific control and report on it.

But when you have too many textbox controls, you can do this

C#
foreach (Control control in this.Controls)
{
    if (control is TextBox && String.IsNullOrWhiteSpace(((TextBox)control).Text))
    {
        //This control is empty. //Do whatever you want here.
        return;
    }
    //You can even check if there are unchecked CheckBoxes or Empty Comboboxes
    if (control is CheckBox && !((CheckBox)control).Checked)
    {
       //This Checkbox is uncheked.
       return;
    }
}
   

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