//Compares the current value of the text box and the properties of the source that is bound,
//return true if modified, false otherwise
public static bool IsChanged(TextBox sender)
{
DependencyObject element = null;
DependencyProperty dp = null;
GetTargetElement(sender, out element, out dp);
if (element == null || dp == null)
{
return(false);
}
BindingExpression bindingExpression = BindingOperations.GetBindingExpression(element, dp);
//using the current BindingExpression, get the string when of the target text property was set to the value of the source
//Otherwise, when StringFormat or converter is set or the type of the property is not a string
//problem happens how to convert it
string propertyValue = PropertyPathHelper.GetTargetValue(bindingExpression);
string elementValue = element.GetValue(dp) as string;
return(!IsSame(propertyValue, elementValue));
}
public static bool UpdateSource(TextBox sender)
{
DependencyObject element = null;
DependencyProperty dp = null;
GetTargetElement(sender, out element, out dp);
if (element == null || dp == null)
{
return(true);
}
BindingExpression bindingExpression = BindingOperations.GetBindingExpression(element, dp);
if (bindingExpression == null)
{
return(true);
}
string elementValue = element.GetValue(dp) as string;
bindingExpression.UpdateSource();
string propertyValue = PropertyPathHelper.GetTargetValue(bindingExpression);
return(IsSame(elementValue, propertyValue));
}