How to change Text of Button field in asp.net using C#

Is it that difficult? I am not sure if this is a client side/server side button control.

For Server Side,

TextBoxName.Text = "whatever";

For Client Side,

TextBoxName.value = "whatever";

Define a Javascript method to OnClientClick property of button.
In the Javascript method, just change the text of the button. Done! Try!


BTW,
I would suggest you to change the text once payment is done and not just on click.

Please try the following:

.aspx

<input id="btnRepayment1" type="submit" value="Repayment" runat="server" onserverclick="btnRepayment1_Click" />
      <asp:Button ID="btnRepayment2" runat="server" Text="Repayment" onclick="btnRepayment2_Click" />

.cs

protected void btnRepayment1_Click(object sender, EventArgs e)
   {
       btnRepayment1.Value = "Paid";
   }
   protected void btnRepayment2_Click(object sender, EventArgs e)
   {
       btnRepayment2.Text = "Paid";
   }

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OP said: I have button fields with Name: repayment as soon as i click the link it should change to paid (text of button)

I see big issue with your requirement. You want to change button text from 'Repayment' to 'Paid'. I don't know anything about your application, but that does not smell right. I am assuming on the button click event you are going to process something, right? So why do you want to change button text before you finish processing? What if the process does complete? Or it throw an exception?

The right thing to do is have some sort of message somewhere to indicate whatever you want to indicate. May be you can disable the button when the user clicks it.