错误CS0103：名称“ ressourcesText”在当前上下文中不存在

Question

I set up a string named ressourcesText, which will be set as the text LblRessources

This is the code for this problem :

public void ressources()
{
    string ressourcesText = "Ressources:"
                        + "\n Wood :" + wood
                        + "\n Stone : " + stone
                        + "\n Wheat : " + wheat
                        + "\n Food : " + food;
}

public void Form1_Load(object sender, EventArgs e)
{ 
    LblRessources.Text = ressourcesText;
}

How can the text for LblRessources use the string ressourcesText? It usually worked this way.

Answer 1

The issue with your code is that ressourcesText is declared locally in the ressources() function.

Variables that are declared within { } brackets are destroyed at the end of the bracket, and are called local variables .

To solve this you could make your variable global:

string ressourcesText;
public void ressources()
{
    ressourcesText = "Ressources:"
                        + "\n Wood :" + wood
                        + "\n Stone : " + stone
                        + "\n Wheat : " + wheat
                        + "\n Food : " + food;
}

public void Form1_Load(object sender, EventArgs e)
{ 
    LblRessources.Text = ressourcesText;
}

Now this isn't necessarily good practice, because at the time of declaring your variable, it will be null, and thus can not be used until you call ressources() .

Another alternative would be to return the variable through the ressources() function and calling it directly to retrieve the value, like follows:

public string ressources()
{
    string ressourcesText = "Ressources:"
                        + "\n Wood :" + wood
                        + "\n Stone : " + stone
                        + "\n Wheat : " + wheat
                        + "\n Food : " + food;
    return ressourcesText;
}

public void Form1_Load(object sender, EventArgs e)
{ 
    LblRessources.Text = ressources();
}

That's somewhat safer.

You should check out these links for more info:

Local variables

C# Methods

Scopes