验证码

[c#]代码库

前台：

<div>
    <asp:TextBox ID="txtCode" runat="server" Width="76px" class="kjia_3" Height="22px"></asp:TextBox>
    <img id="imgVerify" style="width:100px; height:35px;" src="VerifyCode.aspx?'+Math.random()+'" alt="看不清？点击更换" onclick="this.src=this.src+'?'" />

    <asp:Button ID="Button1" runat="server" Text="确定" 
        onclick="Button1_Click1" />
</div>

后台：按钮事件

protected void Button1_Click1(object sender, EventArgs e)
        {
            string code = "";
            code = txtCode.Text.Trim();
            if (String.Compare(Request.Cookies["CheckCode"].Value, code.ToString().Trim(), true) != 0)
            {
                Response.Write("<script>alert('验证码不正确');</script>");
                return;
            }
            else
            {
                Response.Write("<script>alert('正确');</script>");
                return;
            }
        }

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