/// <summary>
/// Routine that can be used read Form Variables into an object if the
/// object name and form variable names match either exactly or with a specific
/// prefix.
///
/// The method loops through all *public* members of the object and tries to
/// find a matching form variable by the same name in Request.Form.
///
/// The routine returns false if any value failed to parse (ie. invalid
/// formatting etc.). However parsing is not aborted on errors so all
/// other convertable values are set on the object.
///
/// You can pass in a Dictionary<string,string> for the Errors parameter
/// to optionally retrieve unbinding errors. The dictionary key holds the
/// simple form varname for the field (ie. txtName), the value the actual
/// exception error message
/// </summary>
/// <remarks>
/// This method can have unexpected side-effects if multiple naming
/// containers share common variable names. This routine is not recommended
/// for those types of pages.
/// </remarks>
/// <param name="Target"></param>
/// <param name="FormVarPrefix">empty or one or more prefixes spearated by |</param>
/// <param name="errors">Allows passing in a string dictionary that receives error messages. returns key as field name, value as error message</param>
/// <returns>true or false if an unbinding error occurs</returns>
public static bool FormVarsToObject(object target, string formvarPrefixes = null, Dictionary <string, string> errors = null)
{
bool isError = false;
List <string> ErrorList = new List <string>();
if (formvarPrefixes == null)
{
formvarPrefixes = "";
}
if (HttpContext.Current == null)
{
throw new InvalidOperationException("FormVarsToObject can only be called from a Web Request");
}
HttpRequest Request = HttpContext.Current.Request;
// try to get a generic reference to a page for recursive find control
// This value will be null if not dealing with a page (ie. in JSON Web Service)
Page page = HttpContext.Current.CurrentHandler as Page;
MemberInfo[] miT = target.GetType().FindMembers(
MemberTypes.Field | MemberTypes.Property,
BindingFlags.Public | BindingFlags.Instance,
null, null);
// Look through all prefixes separated by |
string[] prefixes = formvarPrefixes.Split('|');
foreach (string prefix in prefixes)
{
// Loop through all members of the Object
foreach (MemberInfo Field in miT)
{
string Name = Field.Name;
FieldInfo fi = null;
PropertyInfo pi = null;
Type FieldType = null;
if (Field.MemberType == MemberTypes.Field)
{
fi = (FieldInfo)Field;
FieldType = fi.FieldType;
}
else
{
pi = (PropertyInfo)Field;
FieldType = pi.PropertyType;
}
// Lookup key will be field plus the prefix
string formvarKey = prefix + Name;
// Try a simple lookup at the root first
var strValue = Request.Form[formvarKey];
// if not found try to find the control and then
// use its UniqueID for lookup instead
if (strValue == null && page != null)
{
Control ctl = WebUtils.FindControlRecursive(page, formvarKey);
if (ctl != null)
{
strValue = Request.Form[ctl.UniqueID];
}
}
// Bool values and checkboxes might require special handling
if (strValue == null)
{
// Must handle checkboxes/radios
if (FieldType == typeof(bool))
{
strValue = "false";
}
// other values that are null are not updated
else
{
continue;
}
}
try
{
// Convert the value to it target type
object Value = ReflectionUtils.StringToTypedValue(strValue, FieldType);
// Assign it to the object property/field
if (Field.MemberType == MemberTypes.Field)
{
fi.SetValue(target, Value);
}
else
{
pi.SetValue(target, Value, null);
}
}
catch (Exception ex)
{
isError = true;
if (errors != null)
{
errors.Add(Field.Name, ex.Message);
}
}
}
}
return(!isError);
}
