/// <summary>
/// 验证ViewModel的某一个属性的有效性
/// </summary>
/// <param name="dp"></param>
/// <param name="propertyName"></param>
/// <returns></returns>
public static string ValidateProperty(this ValidationViewModelBase dp, string propertyName)
{
if (string.IsNullOrEmpty(propertyName))
{
return(string.Empty);
}
var targetType = dp.GetType();
var propertyValue = targetType.GetProperty(propertyName).GetValue(dp, null);
return(dp.ValidateProperty(propertyValue, propertyName));
}
/// <summary>
/// 验证整个ViewModel的有性性
/// </summary>
/// <param name="dp"></param>
/// <returns></returns>
public static bool ValidateViewModel(this ValidationViewModelBase dp)
{
string strValid = string.Empty;
var props = dp.GetType()
.GetProperties()
.Where(p => ((ValidationAttribute[])p.GetCustomAttributes(typeof(ValidationAttribute), true)).Length != 0);
foreach (PropertyInfo item in props)
{
var value = item.GetValue(dp, null);
strValid = dp.ValidateProperty(value, item.Name);
dp.NotityProperChanged(item.Name);
if (strValid != string.Empty)
{
return(false);
}
}
return(true);
}
/// <summary>
/// 验证ViewModel的某一个属性的有效性
/// </summary>
/// <param name="dp">ViewModel</param>
/// <param name="value">值</param>
/// <param name="propertyName">属性名称</param>
/// <returns></returns>
public static string ValidateProperty(this ValidationViewModelBase dp, object value, string propertyName)
{
ValidationContext vc = new ValidationContext(dp, null, null)
{
MemberName = propertyName
};
List <System.ComponentModel.DataAnnotations.ValidationResult> vr = new List <System.ComponentModel.DataAnnotations.ValidationResult>();
if (Validator.TryValidateProperty(value, vc, vr))
{
dp.RemoveError(propertyName);
return(string.Empty);
}
else
{
dp.AddError(propertyName, vr.FirstOrDefault().ErrorMessage);
return(vr.FirstOrDefault().ErrorMessage);
}
}
/// <summary>
/// 验证ViewModel的某一个属性的有效性
/// </summary>
/// <typeparam name="MetadataType"></typeparam>
/// <param name="dp"></param>
/// <param name="propertyName"></param>
/// <returns></returns>
public static string ValidateProperty <MetadataType>(this ValidationViewModelBase dp, string propertyName)
{
if (string.IsNullOrEmpty(propertyName))
{
return(string.Empty);
}
var targetType = dp.GetType();
if (targetType != typeof(MetadataType))
{
TypeDescriptor.AddProviderTransparent(
new AssociatedMetadataTypeTypeDescriptionProvider(targetType, typeof(MetadataType)), targetType);
}
var propertyValue = targetType.GetProperty(propertyName).GetValue(dp, null);
return(dp.ValidateProperty(propertyValue, propertyName));
}
