如何为一个类创建具有相同属性但值与每个对象不同的多个对象

Question

protected void page load()
{
    blick=1;
    j=0;
}

protected button1_click()
{
    bclick=blick+1;
    j=j+1;
    ReferenceDetails[]rfobj=new ReferenceDetails[bclick];
    if(j<=bclick)
    {
        rfobj[j]=new ReferenceDetails();
        rfobj[j].name=txtrfname.text;
        rfobj[j].lastname=txtrflastname.text;
    }
}

protected preview button_click()
{
    Response.write(rfobj[1].name); // HOW i should achieve this
    Response.write(rfobj[2].name);
    //object reference is not set to instance of an object
}

I want to create a new object for the same class with same properties but values are different. On Button first click one object want to create with some properties and bind with values according to user enters.

If the button clicked once again then again a new object wants to be created with same properties but different values what user enters at that time and those values want to bind with that corresponding object.

Then I want to get the each newly generated object with their associated values in another button click to show it to on Gridview. But object is generating newly in the above code as rfobj[1], rfobj[2] , but when I go to next button and access that values their will be null.

How do I overcome it? Can anyone provide me with a solution for this problem?

Answer 1

the rfobj array is being created fresh on each button click, so each time it only has the last entry in it

You need to move it to the form - like the 'blick' counter.

Answer 2

This is far away from good programming technique, and may be you are having memory leaks...

but to solve your question, the problem is:

when you click the button second time, the array is recreated, with the number of buttons, but you fill only the last button, the prior buttons remaisn null, because is anew object.

you must backup your reference before recreate, and then fill the previous array slots with previous created objects...

something like this:

in the form:

ReferenceDetails[] rfobj;
int bclick = 0;

in the button:

int old_count = bclick;

bclick=blick+1;
//j=j+1;

ReferenceDetails[] old_rfobj = rfobj;
rfobj = new ReferenceDetails[bclick];

for ( int i = 0; i < old_count; i++ ){

    rfobj[i] = old_rfobj[i];
}

if (j<=bclick) {
    //rfobj[j]=new ReferenceDetails(); you dont need this
    rfobj[bclick-1].name=txtrfname.text;
    rfobj[bclick-1].lastname=txtrflastname.text;
}

This shold work for you, but you may try understand what happens in background, when create and release objects... the new word requests memory from system... and this memory must be released anywhen...

Best regards