C# Check if textbox == textbox

Question

Why does this not work :

            if (This_Ver.Text == New_Ver.Text)
            {
                MAIN_PANEL.Visible = true;
            }
            else if (This_Ver.Text != New_Ver.Text)
            {
            DialogResult dialogResult = MessageBox.Show("An update has been found!" + Environment.NewLine + "Would you like to download and install it?", "Update found!", MessageBoxButtons.YesNo, MessageBoxIcon.Information);
            if (dialogResult == DialogResult.Yes)
            {
                MAIN_PANEL.Visible = false;
                UPDATE_PANEL.Visible = true;
                USERNAME_TEXT.Enabled = false;
                PASSWORD_TEXT.Enabled = false;
                LOGIN_BUTTON.Enabled = false;
                MAIN_PANEL.Visible = false;
                UPDATE_NOW_BUTTON.Enabled = true;
            }
            else if (dialogResult == DialogResult.No)
            {
                UPDATE_NOW_BUTTON.Enabled = true;
                MAIN_PANEL.Visible = true;
            }
        }

I am trying to compare the new version and the current running version. It should open the updater panel when the textboxes does not contain the same version.

But It doesn't work. It always opens the updater panel.

EDIT :

value : This_Ver.Text : V1.1.13.1

value : New_Ver.Text : V1.1.13.1

First thing first, you do not need to check again, once you are in else block, talking about line 4, it will only have else {...} — Yahya, Apr 12 '13 at 10:34
It updates This_Ver.Text on form load : This_Ver.Text = Application.CurrentVersion(); — Menno van Leeuwen, Apr 12 '13 at 10:44
Form.Load Event Occurs before a form is displayed for the first time. Is it possible that your code runs before that? Because your code is ok and it is the most possible issue — Dmitrii Dovgopolyi, Apr 12 '13 at 10:45
Try putting a breakpoint on the first if statement and see what the comparison returns. — Jamie Kelly, Apr 12 '13 at 10:46

score 2 · Accepted Answer · answered Apr 12 '13 at 10:52

2

Try like below may be it will help you you..

change your code

FROM :

if (This_Ver.Text == New_Ver.Text)

TO :

if (This_Ver.Text.ToUpper().Trim().Equals(This_Ver.Text.ToUpper().Trim()))

answered Apr 12 '13 at 10:52

Pandian

8,848
2
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This fixed my problem thanks. But I have one last question what does Trim? – Menno van Leeuwen Apr 12 '13 at 10:55
Trim() - is String function that eliminates leading and trailing whitespace of a string.. try this link for full details... http://msdn.microsoft.com/en-us/library/t97s7bs3.aspx – Pandian Apr 12 '13 at 10:57
Hmmm intresting, Thanks a lot. – Menno van Leeuwen Apr 12 '13 at 10:58
@Pandian: The most common method for string comparisons is using `==` There are small differences in the behavior of using`equal' that the string be non-null. This can be problematic in certain algorithms, but good in others. refer sir jon skeet's answer http://stackoverflow.com/questions/3678792/are-string-equals-and-operator-really-same and http://www.dotnetperls.com/string-equals – Satinder singh Apr 12 '13 at 11:12
@Satindersingh: Yes i agree with you most string comparison methods have `==` and `String.Compare`. but i have mostly used `Equals` in my Program so i have suggest this method too... – Pandian Apr 12 '13 at 11:22

Satinder singh · Answer 2 · 2013-04-12T10:49:27.760

1

Try Something like this

string value1 = This_Ver.Text.Trim();
string value2 = New_Ver.Text.Trim();
if(value1  == value2 )
 {
   //hide your panel
 }
 else
 {
    // code something
 }

if value matches it hides otherwise it goes to else part where you do some logic code.

Aslo want to know what values are you getting in value1,value2 while debugging on IF Condition

edited Apr 12 '13 at 10:49

answered Apr 12 '13 at 10:40

Satinder singh

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16
60
102

Thats code is the code I got there now It still doesn't work :S – Menno van Leeuwen Apr 12 '13 at 10:46
@Nobleleader13245: after using trim() u still getiing problm ? – Satinder singh Apr 12 '13 at 10:56
No your fix works aswell I combined the two fixes thanks you aswell – Menno van Leeuwen Apr 12 '13 at 10:57

score 0 · Answer 3 · answered Apr 12 '13 at 10:40

0

You must use (This_Ver.Text.Equals(New_Ver.Text)) because == comparator will not work. As in Java, == comparator do object references comparation. In contrast, Equals method compares strings content.

Good Luck.

answered Apr 12 '13 at 10:40

emigue

492
3
13

2

== comparator has been overridden for String class. – Thomas Apr 12 '13 at 10:43
You are right Thommas. Thanks you. [Docummentation](http://msdn.microsoft.com/en-us/library/vstudio/362314fe(v=vs.100).aspx) – emigue Apr 12 '13 at 10:50

C# Check if textbox == textbox

3 Answers3