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逮到mono asp.net的bug——多行文本框呈现内容前面有空格

作者：V君 发布于：2015-3-12 23:34 Thursday 分类：折腾手记

这个问题只有用它的人才会遇到, 也不多扯了, 直接贴代码!

[ValidationProperty("Text")]
[ControlValueProperty("Text")]
[DefaultProperty("Text")]
public class TextArea: WebControl, IPostBackDataHandler, IEditableTextControl
{
    protected override HtmlTextWriterTag TagKey
    {
        get { return HtmlTextWriterTag.Textarea; }
    }

    public bool CausesValidation
    {
        get
        {
            if (ViewState["CausesValidation"] == null)
                return false;
            return (bool)ViewState["CausesValidation"];
        }
        set
        {
            ViewState["CausesValidation"] = value;
        }
    }

    public string ValidationGroup
    {
        get
        {
            return (string)ViewState["ValidationGroup"] ?? "";
        }
        set
        {
            ViewState["ValidationGroup"] = value;
        }
    }

    public string Text
    {
        get
        {
            return (string)ViewState["Text"] ?? "";
        }
        set
        {
            ViewState["Text"] = value;
        }
    }

    public bool ReadOnly
    {
        get
        {
            if (ViewState["Readonly"] == null)
                return false;

            return (bool)ViewState["Readonly"];
        }
        set
        {
            ViewState["Readonly"] = value;
        }
    }

    public int Rows
    {
        get
        {
            if (ViewState["Rows"] == null)
                return 0;
            return (int)ViewState["Rows"];
        }
        set
        {
            ViewState["Rows"] = value;
        }
    }

    public int Columns
    {
        get
        {
            if (ViewState["Columns"] == null)
                return 0;
            return (int)ViewState["Columns"];
        }
        set
        {
            ViewState["Columns"] = value;
        }
    }

    protected override void AddAttributesToRender(HtmlTextWriter writer)
    {
        writer.AddAttribute(HtmlTextWriterAttribute.Name, UniqueID);

        if (Enabled && !IsEnabled)
            writer.AddAttribute(HtmlTextWriterAttribute.Disabled, "disabled");
        if (ReadOnly)
            writer.AddAttribute(HtmlTextWriterAttribute.ReadOnly, "readonly");

        if (Rows != 0)
            writer.AddAttribute(HtmlTextWriterAttribute.Rows, Rows.ToString());
        if (Columns != 0)
            writer.AddAttribute(HtmlTextWriterAttribute.Cols, Columns.ToString());

        base.AddAttributesToRender(writer);
    }

    public override void RenderControl(HtmlTextWriter writer)
    {
        RenderBeginTag(writer);
        writer.WriteEncodedText(Text);
        RenderEndTag(writer);
    }

    public bool LoadPostData(string postDataKey, NameValueCollection postCollection)
    {
        var strPostBack = postCollection[postDataKey];
        if (ReadOnly || Text.Equals(strPostBack, StringComparison.Ordinal))
            return false;
        Text = strPostBack;
        return true;
    }

    public void RaisePostDataChangedEvent()
    {
        if (!Page.IsPostBackEventControlRegistered)
        {
            Page.AutoPostBackControl = this;
            if (CausesValidation)
                Page.Validate(ValidationGroup);
        }
        TextChanged(this, EventArgs.Empty);
    }

    public event EventHandler TextChanged = delegate { };
}

标签: 软件开发 C# bug ASP.NET WebForm mono