How to pass a value from one Class file to another Class ???

Question

Hi Req: I want to pass the value from one class to another class file. Example: ClassA.cs having one property like 'ProductId'. i require this value in my second class -> ClassB.cs. Using this value i am doing some calculation in my ClassB (May be ClassB update this property value too). Then again i am returning to my ClassA. My object life-cycle is like ClassA --> ClassB --> ClassA Please share some ideas to retain this prperty value.

Madhu K · Answer

Take a property in class2 private string _ProductId; public string ProductIdNEW { get { return _ProductId; } set { _ProductId = value; } } class ClassB { public void CheckConstraint(string Userid) { ClassA objClassA = new ClassA(); if ( objClassA.ProductId .Equals(string.Empty)) { objClassA.ProductId = APB12341; ProductIdNEW = Class1.ProductId; } } } class ClassA { private string _ProductId; public string ProductId { get { return _ProductId; } set { _ProductId = value; } } public void GetDetails(string Userid) { if(Userid.Equals(string.Empty)) { ProductId=APB12345; } ClassB objClassB = new ClassB (); objClassB.CheckConstraint(Userid); // You get the productid value in id below string id = objClassB.ProductIdNEW; } }

Crish · Answer

Hi I have same problem .thanks for code now it will help me to solve my issue of o pass a value from one Class file to another Class.

Sharrangas · Answer

Yes thanks a lot. Now i am able to access the value without declaring variable as static.

Madhu K · Answer

From the code in classB you will get the product id as APB12345 .

Sharrangas · Answer

I am not getting the value. :(. Is there any option to avoid same static property object shared between the request... ?

Sharrangas · Answer

Yes i can avoid the null ref exception as you mentioned. but as per my requirement i want to update the productId from the classB method. So ClassA.ProductId should not be null object when i call from ClassB. If i declaring this ProductId as static variable the object exist. So i can able to update my productId as per my wish. so same like this i want to retain the object without declaring property as static.(the reason for avoiding static variable - if i am declaring property as static the same object shared with all request. So i want to avoid that....)

Madhu K · Answer

change this if ( ClassA.ProductId .Equals(string.Empty)) to if (Class1.ProductId==null || Class1.ProductId==) or if(string.IsNullOrEmpty(Class1.ProductId)) to check for null.

Sharrangas · Answer

I will explain my requirement clearly. My aspx: string Userid = string.Empty; ClassA objClassA = new ClassA(); objClassA.GetDetails(Userid); --------------- class ClassA { private string _ProductId; public string ProductId { get { return _ProductId; } set { _ProductId = value; } } public void GetDetails(string Userid) { if (Userid.Equals(string.Empty)) { _ProductId = APB12345; } ClassB objClassB = new ClassB(); objClassB.CheckConstraint(Userid); } } -------------------------- class ClassB { public void CheckConstraint(string Userid) { ClassA objClassA = new ClassA(); if ( objClassA.ProductId .Equals(string.Empty)) { objClassA.ProductId = APB12341; } } }------------ when my breakpoint reaches the ClassA.ProductId its returning with Null refer exeception. If i declare the ProductId as static it will work but i dont want that.... Please suggest me how to get the object without using static declartion?

Madhu K · Answer

Use properties with get set to access the values between the class. check the sample class Class1 { private int ProductId = 20; public int intPublicProperty { get {return ProductId ;} set { ProductId = value;} } } class class2 { public void Checkvalue() { Class1 objClass1 = new Class1(); MessageBox.Show(Showing in Class Two :  + objClass1.intPublicProperty); } }