Question

我有一个名为＆＃34; Staff＆＃34;的表，在该表中我有一个名为＆＃34; ProfilePicture＆＃34;的实体。包含编码的Base64图像字符串。

如何解码base64图像并在下面的gridview中显示？

<asp:GridView ID="staffgrid" runat="server" AutoGenerateColumns="False" DataKeyNames="Staff_ID" DataSourceID="staffdb">
        <Columns>
            <asp:BoundField DataField="Staff_ID" HeaderText="ID" ReadOnly="True" SortExpression="Staff_ID"></asp:BoundField>
            <asp:BoundField DataField="ProfilePicture" HeaderText="ProfilePicture" ReadOnly="true" SortExpression="ProfilePicture">
                <ItemStyle Width="100px"></ItemStyle>
            </asp:BoundField>
            <asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name"></asp:BoundField>
            <asp:BoundField DataField="Gender" HeaderText="gender" SortExpression="Gender"></asp:BoundField>
            <asp:BoundField DataField="Email" HeaderText="email" SortExpression="Email"></asp:BoundField>
            <asp:BoundField DataField="Password" HeaderText="password" SortExpression="Password"></asp:BoundField>
            <asp:CommandField ShowDeleteButton="True" ShowEditButton="True" ButtonType="Button" ShowHeader="True" HeaderText="Edit"></asp:CommandField>
            <asp:ImageField></asp:ImageField>
        </Columns>
    </asp:GridView>
    <asp:SqlDataSource runat="server" ID="staffdb" ConnectionString='<%$ ConnectionStrings:conStr %>' SelectCommand="SELECT [Staff_ID], [Name], [Email], [Password], [Gender], [ProfilePicture] FROM [Staff]"></asp:SqlDataSource>

我在互联网上找到了一个函数，它接受一个字符串，并在一个名为img的变量中返回图像，但我无法弄清楚如何实现它。

Function Base64ToImage(ByVal base64string As String) As System.Drawing.Image
        'Setup image and get data stream together
        Dim img As System.Drawing.Image
        Dim MS As System.IO.MemoryStream = New System.IO.MemoryStream
        Dim b64 As String = base64string.Replace(" ", "+")
        Dim b() As Byte

        'Converts the base64 encoded msg to image data
        b = Convert.FromBase64String(b64)
        MS = New System.IO.MemoryStream(b)

        'creates image
        img = System.Drawing.Image.FromStream(MS)

        Return img
    End Function

Answer 1

您不需要将base64字符串转换为System.Drawing.Image。您只需将它作为字符串显示在GridView中即可。

<asp:TemplateField>
    <ItemTemplate>
        <img src="data:image/jpeg;base64,<%# Eval("ProfilePicture") %>" />
    </ItemTemplate>
</asp:TemplateField>

解码Base64图像并在gridview中显示它

1 个答案: