Sum Of textboxes values

Saurabh Pandey

13y2.6kLearn iOS Programming

this is my code

int sum = int.Parse(TextBox5.Text) + int.Parse(TextBox6.Text) + int.Parse(TextBox7.Text);

Label1.Text = String.Format("{0}", sum);

when I enter all three textboxes it runs clearly but if i keep any one or two of them null it gives error...

input was not in correct formate ..

how can I solve this error.....

5 Replies

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Srinubabu Ravilla13y ago
Try this
int val1;
int val2;
int val3;
int.TryParse(TextBox5.Text, out val1);
int.TryParse(TextBox6.Text, out val2);
int.TryParse(TextBox7.Text, out val3);

Label1.Text = String.Format("{0}", val1+val2+val3);
Shankar M13y ago
Hi Saurabh,

int.TryParse Method tries to convert the given Input to a number returning a boolean (true/false) value.

If the return value is true - It is a valid Number

If the return equals to false - The Input is not a number , that is Invalid.

Please try this,

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace PerformAdd
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e)
{

int result;

bool validInput = int.TryParse(textBox1.Text, out result);

if (!int.TryParse(textBox1.Text, out result))
{
MessageBox.Show("Invalid Input TextBox1");
}
else if (!int.TryParse(textBox2.Text, out result))
{
MessageBox.Show("Invalid Input TextBox2");
}
else if (!int.TryParse(textBox3.Text, out result))
{
MessageBox.Show("Invalid Input TextBox3");
}
else
{
int x = Convert.ToInt16(textBox1.Text);
int y = Convert.ToInt16(textBox2.Text);
int z = Convert.ToInt16(textBox3.Text);

int SumofInputs = x + y + z;
label1.Text = SumofInputs.ToString();
}

}
}
}

Regards,
Shankar M
Satyapriya Nayak13y ago
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace Add
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void btnadd_Click(object sender, EventArgs e)
        {
            int i, j,k;
            int.TryParse(textBox1.Text, out i);
            int.TryParse(textBox2.Text, out j);
            int.TryParse(textBox3.Text, out k);
            int result = i + j + k;
            label1.Text = result.ToString();
        }
    }
}
Gajendra Yadav13y ago
You are getting this error because you are trying to convert string type to integer type. by default textbox contains empty string(" ") that can not be converted to int type.

Before sum do validation if textbox is not emty the add this.
or
You Use int.TryParse() method instead of int.Parse or convert.Toint32 method.

I hope it will help you
Shankar M13y ago
Hi Saurabh,

It is best Practise to use int.TryParse method.

Please view this link,

http://www.homeandlearn.co.uk/csharp/csharp_s3p9.html

Thanks & Regards,
Shankar M