從MDI父項傳遞一個字符串到孩子的模態對話框

Question

如何將一個字符串從MDI父項傳遞給孩子的模態對話框？

MDI父代碼打開孩子：

Form1 f1 = new Form1(); 
f1.MdiParent = this; 
f1.Show(); 

Form1的代碼來打開模態對話框

Form2 f2= new Form2(); 
f2.ShowDialog(); 

Answer 1

如果你總是使用形式爲模式的形式，你可以使用類似的模式這個。

class FormResult 
    { 
     public DialogResult dr {get; private set;} 
     public string LastName {get; private set;} 
     public string FirstName {get; private set;} 
    } 

    class MyForm : whatever 
    { 
     static public FormResult Exec(string parm1, string parm2) 
{ 
     var result = new FormResult(); 
     var me = new MyForm(); 
     me.parm1 = parm1; 
     me.parm2 = parm2; 
     result.dr = me.ShowDialog(); 
     if (result.dr == DialogResult.OK) 
     { 
     result.LastName = me.LastName; 
     result.FirstName = me.FirstName; 
     } 
     me.Close(); // should use try/finally or using clause 
     return result; 
    } 
} 

... rest of MyForm 

這種模式在隔離您使用窗體的「私有」數據的途徑，並且可以很容易地 如果您決定添加MORS返回值延長。如果您有更多的一對夫婦的輸入參數，你可以捆綁它們放到一個類，並通過該類的實例來Exec方法

Answer 2

只是通過它通過在每個級別使用特性：

//Form1 needs a property you can access 
public class Form1 
{ 
    private String _myString = null; 
    public String MyString { get { return _myString; } } 

    //change the constructor to take a String input 
    public Form1(String InputString) 
    { 
     _myString = InputString; 
    } 
    //...and the rest of the class as you have it now 
} 

public class Form2 
{ 
    private String _myString = null; 
    public String MyString { get { return _myString; } } 

    //same constructor needs... 
    public Form2(String InputString) 
    { 
     _myString = InputString; 
    } 
} 

最終，您的呼叫將變爲：

String strToPassAlong = "This is the string"; 

Form1 f1 = new Form1(strToPassAlong); 
f1.MdiParent = this; 
f1.Show(); 

Form2 f2= new Form2(f1.MyString); //or this.MyString, if Form2 is constructed by Form1's code 
f2.ShowDialog(); 

現在，沿途的每個表格都有您傳遞的字符串的副本。