索引超出了数组界限。

[ivanho]

using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.IO;

public partial class _Default : System.Web.UI.Page
{

protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{

Boolean fileok = false;
string path = Server.MapPath("~/UpFiles/");
if (!Directory.Exists(path))
{
Directory.CreateDirectory(path);
}
if (FileUpload1.HasFile)
{
string fileEx = System.IO.Path.GetExtension(FileUpload1.FileName).ToString();
string[] allEx ={".gif",
"png",
"jpg",
"jpeg"};
for (int i = 0; i <= allEx.Length; ++i)
{
if (fileEx == allEx[i]) --报错是在这里!!
{
fileok = true;
Label1.Text = "开始上传";
}
}
}
if (fileok)
{
try
{
FileUpload1.PostedFile.SaveAs(path + FileUpload1.FileName);
Label1.Text = "文件上传成功！";
}
catch (Exception ex)
{
Label1.Text = "文件上传失败！";
}
}
else
{
Label1.Text = "非法的文件类型！";
}

}
}

[closewbq]

感觉有好几处问题，如果图片的扩展名是大写的，可以吗？
在就是，当循环的时候只要发现匹配的后缀名，直接就break就行了。

[xiaozhangnima]

大哥，这是java区，.net去.net区问

[【如鱼饮水】]

for (int i = 0; i <= allEx.Length; ++i) //=号去掉



for (int i = 0; i < allEx.Length; ++i)

[会游泳的小乌龟]

for (int i = 0; i < allEx.Length; ++i)

[dixiasenlin]

支持2、3楼

[wenbinglove]

for (int i = 0; i <= allEx.Length; ++i) //=号去掉