Index out of bound

Question

I am programming in C# i need to put some things in a string 'xml'

I have the following code

        TextBox[] myTextBoxes = new TextBox[] { this.textBox2, this.textBox3, this.textBox4, this.textBox5, this.textBox6, this.textBox7, this.textBox8, this.textBox9, this.textBox10, this.textBox11 };
        TextBox[] ValueBoxes = new TextBox[] { this.textBox3, this.textBox5, this.textBox7, this.textBox9, this.textBox11 };
        CheckBox[] myCheckBoxes = new CheckBox[] { this.checkBox2, this.checkBox4, this.checkBox6, this.checkBox8, this.checkBox10 };
        CheckBox[] myMandBoxes = new CheckBox[] { this.checkBox3, this.checkBox5, this.checkBox7, this.checkBox9, this.checkBox11 };

and to verify certain condition i have

 xml += "<fields>";

        for (int i = 0; i < myTextBoxes.Length; i++)
        {
            if (string.IsNullOrWhiteSpace(myTextBoxes[i].Text))
            {
                if (myCheckBoxes[i].Checked == true)
                    xml += "<field display='yes'> ";
                else
                    xml += "<field display='no'> ";
                if (myMandBoxes[i].Checked == true)
                    xml += "<mandatory='yes'>";
                else
                    xml += "<Mandatory='no'>";
                xml += "<label>" + (string)myTextBoxes[i].Text + "</label>";

            }
        }

It gives me an Indexoutof boud exception at if (myCheckBoxes[i].Checked == true)

How can i resolve this

Answer 1

Your arrays have different amounts of elements in them so you cannot access them all by using the same index. They will have to be done independently.

Answer 2

You don't have same number of checkboxes as Textboxes so you can't access them against the same index. Your index is starting from 0 to myTextBoxes.Length, if i is going to be greater than 4, then you will get this exception.

Not really sure what you are trying to do but you can add a check against the length before accessing the element from myCheckBoxes.

if (i < myCheckBoxes.Length && myCheckBoxes[i].Checked == true)
        xml += "<field display='yes'> ";

Answer 3

Use Foreach instead

Here edit as myTextBoxes.Length - 1

for (int i = 0; i < myTextBoxes.Length - 1; i++) 

EDIT:

Also your checkBox count and Textox count does not tally

Answer 4

Your for loop is running to myTextBoxes.length, but you are iterating through myCheckBoxes. It seems you have more textboxes than CheckBoxes

Change it to:

for (int i = 0; i < myCheckBoxes.Length; i++) {

Answer 5

Instead of

for (int i = 0; i < myTextBoxes.Length; i++)

use

for (int i = 0; i < myCheckBoxes.Length; i++) // or myMandBoxes.Length (Both the CheckBoxes have same items)

Because you are looping with CheckBoxes so why having a length of TextBox.

Answer 6

Your text box has 11 elements, while checkbox has 5 elements.

Change following

 if (string.IsNullOrWhiteSpace(myTextBoxes[i].Text))

to

 if (string.IsNullOrWhiteSpace(myTextBoxes[i].Text) && i < myCheckBoxes.Length )

Answer 7

First of all, never use += on strings when constructing them with loops, they are immutable, and using it this way, it's just a waste of speed and memory. Use a StringBuilder instance instead.

As for your question, the length of the myTextBoxes array is 10, so you have items at indexes 0 through 9. The code in this line

if (myCheckBoxes[i].Checked == true)

tries to access the corresponding item in the myCheckBoxes array that has 5 elements (indexed 0 to 4). When i becomes 5, the code accesses the myCheckBoxes[5] that does not exist, hence the exception.

Other than that, textBox2 or checkBox7 are simply awful names for controls, and there are better options in the .net Framework for XML serialization and generation.