如何使用数组成员？

Question

为什么在 struct 中使用 struct array 时会出现错误？

public struct Tables
{
    public string name;
}

public struct Schema
{
    public string name;
    public Tables[] tables; //Declarate struct array in struct
}

我在这段代码中使用了struct：

Schema schema;

private void Form1_Load(object sender, EventArgs e)
{
    schema.name = "schemaName";
    schema.tables[0].name = "tables1Name"; // Error in here: Object reference not set to an instance of an object
}

Answer 1

您需要初始化数组：

schema.name = "schemaName";
schema.tables = new Tables[10];
schema.tables[0].name = "tables1";

Answer 2

这是因为schema.tables从未初始化，因此为空

试

private void Form1_Load(object sender, EventArgs e)
{
    schema.name = "schemaName";
    schema.tables = new Tables[5];
    schema.tables[0].name = "tables1"; // Error ini here: Object reference not set to an instance of an object
}