DevForce 2010: Retreive max string length at runtime

Retreive max string length at runtime

Printed From: IdeaBlade
Category: DevForce
Forum Name: DevForce 2010
Forum Discription: For .NET 4.0
URL: http://www.ideablade.com/forum/forum_posts.asp?TID=2571
Printed Date: 23-Apr-2024 at 3:02am

Topic: Retreive max string length at runtime

Posted By: chuckc
Subject: Retreive max string length at runtime
Date Posted: 20-Mar-2011 at 6:01pm

Simple question:

How does one retrieve the max length of a entity string field at runtime? I see the value provided to the StringLengthVerifier, but what is the technique to get that value for use in my own code?

  /// <summary>Gets or sets the Description. </summary>
    [Bindable(true, BindingDirection.TwoWay)]
    [Editable(true)]
    [Display(Name="Description", AutoGenerateField=true)]
    [IbVal.StringLengthVerifier(MaxValue=1000, IsRequired=false, ErrorMessageResourceName="AccountTransactionDetail_Description")]
    [DataMember]
    public string Description {
      get { return PropertyMetadata.Description.GetValue(this); }
      set { PropertyMetadata.Description.SetValue(this, value); }
    }

Thanks!

Replies:

Posted By: sbelini
Date Posted: 21-Mar-2011 at 2:31am

Hi Chuck,

Unfortunatelly this is not a trivial task. You will need to retrieve this information from the EDMX. There is some information on how to do this at http://blogs.msdn.com/b/adonet/archive/2008/01/24/how-to-extract-csdl-from-edmx.aspx - http://blogs.msdn.com/b/adonet/archive/2008/01/24/how-to-extract-csdl-from-edmx.aspx .

The link above has been posted in a previous thread at http://www.ideablade.com/forum/forum_posts.asp?TID=2403&KW=maxlength&PID=9482&title=fixedlength-fields - http://www.ideablade.com/forum/forum_posts.asp?TID=2403&KW=maxlength&PID=9482&title=fixedlength-fields , where someone had a similar question.

I hope it helps,

Silvio.

Posted By: sbelini
Date Posted: 21-Mar-2011 at 10:44am

Hello again Chuck,

You might actually be able to do that by using reflection:

public void GetMaxStringLengthSample() {

var maxStringLength = GetMaxStringLengthAttribute(typeof(Customer),

Customer.PropertyMetadata.CompanyName.Name);

Assert.IsTrue(maxStringLength == 40, "This should not fail");

}

public int GetMaxStringLengthAttribute(Type entityType, String propertyName) {

var propertyInfo = entityType.GetProperty(propertyName);

var attributes = (StringLengthVerifierAttribute)propertyInfo

.GetCustomAttributes(typeof(StringLengthVerifierAttribute), false).First();

return attributes.MaxValue;

}

You can also find this snippet in its original thread at http://www.ideablade.com/forum/forum_posts.asp?TID=2152&title=string-field-maxlength - http://www.ideablade.com/forum/forum_posts.asp?TID=2152&title=string-field-maxlength

Silvio.