INotifyDataErrorInfo不引发错误，其背后的代码已更改 [英] INotifyDataErrorInfo not raising error changed in code behind

问题描述

我正在从后面的代码中获得发布的执行验证.我的数据显示在数据网格中.列(类型)之一是下拉菜单，更改下拉菜单后会触发DropDownClosed事件，该事件将在后面的代码中处理.

I am experiencing issued performing validation from the codebehind. My data is displayed in a datagrid. One of the columns (type) is a drop down and when the drop down menu is changed it triggers a DropDownClosed Event which is handled in the code behind.

我要实现的是验证以下列的内容以匹配下拉列表中新选择的类型.如果不匹配，我希望在网格上显示验证错误.我使用INotifyDataErrorInfo接口实现了验证，除非我在后面的代码中使用它，否则它确实运行良好.当后面的代码调用验证时，永远不会更新datagrid的ValidationSummary.我在这里做错了什么?使用调试器时，我可以清楚地看到错误已添加到接口的错误"词典中.

What I am trying to achieve is to validate the content of the following column to match the newly selected type in the drop down. If it does not match i want a validation error to be displayed on the grid. I implemented my validation using the INotifyDataErrorInfo interface and it works really well except when I use it in the code behind. When the code behind calls the validation the ValidationSummary of the datagrid is never updated. What I am doing wrong here ??? When using the debugger I can clearly see the errors being added to the Errors dictionnary of the interface...

这里是处理程序:

        private void TypeBoxChanged(object sender, EventArgs e)
        {
        ComboBox box = (sender as ComboBox);
        IncomingPolicy row = (IncomingPolicy)box.DataContext;

        string ruleTypeValue = TypeList.GetKeyForText(box.SelectedItem.ToString());
        //check if the type is the same
        if(row.TypeWrapper == ruleTypeValue)
            return;
        if (row.ValidateRule(ruleTypeValue))
        {
            //SAVE the record
        }
        else
        {
            row.RaiseErrorsChanged("RuleWrapper");
        }
    }

validate规则方法将基于ruletypevalue调用此方法

The validate rule method will based on the ruletypevalue call this method

        public bool ValidateRegularExpression(string property, string value, string expression, string errorMessage)
        {
        bool isValid = true;
        Regex regex = new Regex(expression);
        Match match = regex.Match(value);
        if (match.Success)
        {
            RemoveError(property, errorMessage);                
        }
        else
        {
            AddError(property, errorMessage, false);
            isValid = false;
        }

        return isValid;
    }

我遵循了MSDN上的示例实现 http://msdn.microsoft.com/zh-cn/library/system.componentmodel.inotifydataerrorinfo%28VS.95%29.aspx

I followed the sample implementation on MSDN http://msdn.microsoft.com/en-us/library/system.componentmodel.inotifydataerrorinfo%28VS.95%29.aspx

推荐答案

早些时候，我已经实现了验证帮助器，并为接口IDataErrorInfo和INotifyDataErrorInfo创建了示例解决方案:

Some time earlier I've implemented validation helpers and created the sample solution for both interfaces IDataErrorInfo and INotifyDataErrorInfo:

http://vortexwolf.wordpress.com/2011/10/01/wpf-validation-with-idataerrorinfo/

源代码

主要实现在这里:

this.PropertyChanged += (s, e) => 
{
    // if the changed property is one of the properties which require validation
    if (this._validator.PropertyNames.Contains(e.PropertyName))
    {
        this._validator.ValidateProperty(e.PropertyName);
        OnErrorsChanged(e.PropertyName);
    }
}

无论验证是否成功，都应始终调用OnErrorsChanged(或您的情况下的RaiseErrorsChanged)方法:如果属性无效-将显示红色边框，如果有效-绑定控件将为回到正常状态.

You should always call the OnErrorsChanged (or RaiseErrorsChanged in your case) method regardless of success of validation: if the property is invalid - the red border will be displayed, if it is valid - the bound control will be returned to its normal state.

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