將文本框中的值添加到標籤

Question

我想知道如何能夠將文本框中的值添加到標籤中，而不會在每次添加另一個比薩時將標籤重置爲零。我基本上需要代碼才能顯示如何繼續增加文本框值添加到標籤

private void SummaryBox_TextChanged(object sender, EventArgs e)//Textbox:the value is shown of the pizza selected 
     { 

     } 

     private void txtPizzaPrice_TextChanged(object sender, EventArgs e) 
     { 

     } 
     Menu(object sender, System.ComponentModel.CancelEventArgs e) 
{ 


     private void lblPrice_Click(object sender, EventArgs e) 
     { 
      // Label where the Pizza prices needs to be added up each time I press add pizza 
     } 

    } 
} 

//HERE ARE THE PIZZA VALUES 

     double PizzaPrice;//Global 


double ExtraTopping;//Global 

     private void radioButton2_CheckedChanged(object sender, EventArgs e) 
     { 
      string CT; 



      if (radioButton2.Enabled == true) //PIZZA CHEESE TOMATO 
      { 
       double ctp = 3.50; 
       PizzaPrice = ctp; 

       txtPizzaPrice.Text = "£ " + PizzaPrice.ToString(); //Value I want //to add to lblPrice 

       CT = radioButton2.Text; 

       SummaryBox.Text = CT; 


      } 
      else 
      { 
       SummaryBox.Clear(); 
      } 

     } 

     private void radioButton1_CheckedChanged(object sender, EventArgs e) 
     { 
      string VS; 

      if (radioButton1.Enabled == true) //PIZZA Veg SUpreme 
      { 
       double vsp = 5.20; 
       PizzaPrice = vsp; 

       txtPizzaPrice.Text = "£ " + PizzaPrice.ToString(); //Value I want //to add to lblPrice 

       VS = radioButton1.Text; 

       SummaryBox.Text = VS; 

      } 
      else 
      { 
       SummaryBox.Clear(); 
      } 

     } 

     private void radioButton3_CheckedChanged_1(object sender, EventArgs e) 
     { 
      string SV; 


      if (radioButton3.Enabled == true) //PIZZA SPicy Veg 
      { 
       double svp = 5.20; 
       PizzaPrice = svp; 

       txtPizzaPrice.Text = "£ " + PizzaPrice.ToString(); //Value I want //to add to lblPrice 

       SV = radioButton3.Text; 

       SummaryBox.Text = SV; 


      } 
      else 
      { 
       SummaryBox.Clear(); 
      } 
     } 

     private void radioButton6_CheckedChanged(object sender, EventArgs e) 
     { 
      string MF; 

      if (radioButton6.Enabled == true) //PIZZA Veg SUpreme 
      { 
       double mfp = 5.80; 
       PizzaPrice = mfp; 

       txtPizzaPrice.Text = "£ " + PizzaPrice.ToString(); //Value I want //to add to lblPrice 

       MF = radioButton6.Text; 

       SummaryBox.Text = MF; 
      } 
      else 
      { 
       SummaryBox.Clear(); 
      } 
     } 

     private void radioButton7_CheckedChanged(object sender, EventArgs e) 
     { 
      string HP; 

      if (radioButton7.Enabled == true) //PIZZA Ham pineapple 
      { 
       double hpp = 4.20; 
       PizzaPrice = hpp; 

       txtPizzaPrice.Text = "£ " + PizzaPrice.ToString(); 
       ^Value I want to add to lblPrice^ 

       HP = radioButton7.Text; 

       SummaryBox.Text = HP; 

      } 
      else 
      { 
       SummaryBox.Clear(); 

      } 
     } 

     private void radioButton4_CheckedChanged(object sender, EventArgs e) 
     { 
      string SF; 

      if (radioButton4.Enabled == true) // PIZZA Veg SUpreme 
      { 
       double sfp = 5.60; 
       PizzaPrice = sfp; 

       txtPizzaPrice.Text = "£ " + PizzaPrice.ToString(); //Value I want //to add to lblPrice 

       SF = radioButton4.Text; 

       SummaryBox.Text = SF; 

      } 
      else 
      { 
       SummaryBox.Clear(); 
      } 
     } 

Answer 1

我相信你正在嘗試做的是將值添加到PizzaPrice，然後附加到前面的£標誌上txtPizzaPrice.Text顯示。

PizzaPrice應該是property rather than a field。

public double PizzaPrice { get; set; } 

請注意，我+=價值比薩餅的價格，然後在文本屬性顯示出來：

private void radioButton7_CheckedChanged(object sender, EventArgs e) 
{ 
    if (radioButton7.Checked) 
    { 
     double hpp = 4.20; 
     PizzaPrice += hpp; 
     txtPizzaPrice.Text = "£ " + PizzaPrice.ToString(); 
     SummaryBox.Text = radioButton7.Text; 
    } 
    else 
    { 
     SummaryBox.Clear(); 
    } 
} 

你可以做很多事情來縮短你的代碼。嘗試將比薩類型添加到單選按鈕的Tag，並使用一個結構體作爲比薩值。但我會把它留給你。