vs2013 上传碰到的问题：“输入的不是有效的 Base-64 字符串　”

@using (Html.BeginForm("Create", "ImageStore", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
@Html.AntiForgeryToken()

<div class="form-horizontal">
<h4>ImageStoreModels</h4>
<hr />
@Html.ValidationSummary(true)

<div class="form-group">
@Html.LabelFor(model => model.ImageCataloge, new { @class = "control-label col-md-2" })
<div class="col-md-10">

@Html.DropDownListForEnum(model => model.ImageCataloge)
@Html.ValidationMessageFor(model => model.ImageCataloge)
</div>
</div>

<div class="form-group">
@Html.LabelFor(model => model.ImageData, new { @class = "control-label col-md-2" })
<div class="col-md-10">
@*@Html.TextBoxFor(model => model.ImageData, new { type = "file",  style="none"})*@

<input name="ImageData" type="file"  />
@Html.ValidationMessageFor(model => model.ImageData)

<input name="ImageData" id="ImageData" type="file" />
</div>
</div>

<div class="form-group">
@Html.LabelFor(model => model.ImageAlt, new { @class = "control-label col-md-2" })
<div class="col-md-10">
@Html.EditorFor(model => model.ImageAlt)
@Html.ValidationMessageFor(model => model.ImageAlt)
</div>
</div>

<div class="form-group">
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Create" class="btn btn-default" />
</div>
</div>
</div>
}