Question

Hi I have something like:
Version 1:

bool noErrors = true;
while(noErrors)
{
   noErrors = ValidateControl(txtName);

   // other code
}

Version 2:

bool noErrors = true;
while(noErrors)
{
   if(!ValidateControl(txtName)) break;

   // other code
}

I use this code to validate a form and if the validation returns false, I want to break before executing “other code”. Since I do not know when the loop checks for its condition, I do not know which makes more sense. Should I use the first or the second version, or maybe a third one?

Thank you for your time

Answer 1

Version 2 will break before running the //other code. Version 1 will not check until the start of the next iteration.

bool noErrors = true;
while(noErrors) 
{    
    noErrors = ValidateControl(txtName);     
    // other code 
}

Checks before each iteration.

bool noErrors = true;
do 
{    
    noErrors = ValidateControl(txtName);     
    // other code 
} while(noErrors);

Checks after each iteration.

Neither check during an iteration. As stated by the other answerers, the following code simplifies the example but makes me ask the question, is the validity of txtName likely to change during the execution of the loop? Would some other limiting condition be more useful?

while (ValidateControl(txtName)) 
{
    // other code 
} 

If the validity of txtName will not change, consider,

if (ValidateControl(txtName))
{
  while(/*Some other condition*/)
  {
      // other code
  }
}