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; this.button1.TabIndex = 0;
this.button1.Text = "显示输出";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// label1
//
this.label1.Location = new System.Drawing.Point(8, 48);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(456, 336);
this.label1.TabIndex = 1;
this.label1.Text = "label1";
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
this.ClientSize = new System.Drawing.Size(480, 405);
this.Controls.Add(this.label1);
this.Controls.Add(this.button1);
this.MaximizeBox = false;
this.MinimizeBox = false;
this.Name = "Form1";
this.Text = "Ref & Out";
this.ResumeLayout(false);
}
#endregion
/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
int[] firstArray = {1, 2, 3};
int[] firstArrayCopy = firstArray;
this.label1.Text = "Test Passing firstArray reference by value";
this.label1.Text += "nnContents of firstArray before calling FirstDouble:nt";
for(int i = 0;i < firstArray.Length; i++)
{
this.label1.Text += firstArray[i] + " ";
}
FirstDouble(firstArray);
this.label1.Text += "nnContents of firstArray after calling FirstDouble.nt";
for(int i=0;i<firstArray.Length;i++)
{
this.label1.Text += firstArray[i] + " ";
}
if(firstArray == firstArrayCopy)
this.label1.Text +="nnThe references refer to the same array.n";
else
this.label1.Text +="nnThe reference refer to different arrays.n";
int[] secondArray = {1, 2, 3};
int[] secondArrayCopy = secondArray;
this.label1.Text += "nTest passing secondArray reference by reference.";
this.label1.Text += "nnContents of secondArray before calling SecondDouble:nt";
for(int i=0;i<secondArray.Length; i++)
{
this.label1.Text += secondArray[i] + " ";
}
SecondDouble(ref secondArray);
this.label1.Text +="nnContents of secondArray after calling SecondDouble:nt";
for(int i=0; i<secondArray.Length;i++)
{
this.label1.Text += secondArray[i] + " ";
}
if(secondArray== secondArrayCopy)
this.label1.Text += "nnThe reference refer to the same array.";
else
this.label1.Text += "nnThe reference refer to different arrays.";
this.label1.Text += "n___________________heshi_________________nsecondarrayn";
for(int i = 0;i<secondArray.Length;i++)
{
this.label1.Text += secondArray[i] + " ";
}
this.label1.Text +="nsecondarraycopyn";
for(int i=0;i<secondArrayCopy.Length;i++)
{
this.label1.Text += secondArrayCopy[i] + " ";
}
}
void FirstDouble(int[] array)
{
for(int i = 0;i<array.Length;i++)
array[i] *= 2;
array = new int[] {11, 12, 13};
}
void SecondDouble(ref int[] array)
{
for(int i=0;i<array.Length;i++)
{
array[i] *= 2;
}
array = new int[] {11, 12, 13};
}
}
}
运行后的结果是： 
这个就说明了被调用的程序已经改变了原有的Reference。
总结
总的说来，Ref和Out这两个关键字都能够提供相似的功效，其作用也很像C中的指针变量。稍有不同之处是：
使用Ref型参数时，传入的参数必须先被初始化。而Out则不需要，对Out而言，就必须在方法中对其完成初始化。
使用Ref和Out时都必须注意，在方法的参数和执行方法时，都要加Ref或Out关键字。以满足匹配。
Out更适合用在需要Return多个返回值的地方，而Ref则用在需要被调用的方法修改调用者的引用的时候。
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