小编k78*_*787的帖子

为什么'fopen'返回NULL指针?

我正在使用C编程语言编写一个简单的文件分割器/合并程序.问题是,由于某种原因,fopen返回NULL,因此,我的程序在fwrite语句中崩溃.我该如何解决?

这是C文件:

int SplitFile(char* filename, char* output, size_t size)
{
    char current_file_name[256];
    int file_count = 0, i = 0;
    FILE *file = fopen( filename, "rb" );
    printf("split %s into chunks of %d named\n", filename, size);

    if (!file)
       return E_BAD_SOURCE;
    else
    {
        output = (char *) malloc(size * sizeof(char));
        if (output == NULL)
            return E_NO_MEMORY;
        else
        {
            int bytes_read = 0;
            FILE *outFile;
            do
            {
                bytes_read = fread(output, sizeof(char), size, file );
                sprintf(current_file_name, "%s%04lu\n", "part", file_count++);
                outFile …
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c null fopen fwrite

14
推荐指数
2
解决办法
7万
查看次数

C#XMLreader和子节点

我有这个xml文件.

           <movies>
             <movie>
               <score>8.582207</score>
               <popularity>3</popularity>
               <translated>true</translated>
               <adult>false</adult>
               <language>en</language>
               <original_name>Transformers</original_name>
               <name>Transformers</name>
               <alternative_name>The Transformers</alternative_name>
               <type>movie</type>
               <id>1858</id>
               <imdb_id>tt0418279</imdb_id>
               <url>http://www.themoviedb.org/movie/1858<;/url>
               <votes>28</votes>
               <rating>7.2</rating>
               <certification>PG-13</certification>
               <overview>The Earth is caught in the middle of an intergalactic war /overview>
               <released>2007-07-04</released>
               <images>
                    <image type="poster" url="http://hwcdn.themoviedb.org/posters/304/4bc91347017a3c57fe007304/transformers-original.jpg" size="original" id="4bc91347017a3c57fe007304"/>
                    <image type="poster" url="http://hwcdn.themoviedb.org/posters/304/4bc91347017a3c57fe007304/transformers-mid.jpg" size="mid" id="4bc91347017a3c57fe007304"/>
                    <image type="poster" url="http://hwcdn.themoviedb.org/posters/304/4bc91347017a3c57fe007304/transformers-cover.jpg" size="cover" id="4bc91347017a3c57fe007304"/>
                    <image type="poster" url="http://hwcdn.themoviedb.org/posters/304/4bc91347017a3c57fe007304/transformers-thumb.jpg" size="thumb" id="4bc91347017a3c57fe007304"/>
                    <image type="backdrop" url="http://hwcdn.themoviedb.org/backdrops/2ce/4bc91339017a3c57fe0072ce/transformers-original.jpg" size="original" id="4bc9133s9017a3c57fe0072ce"/>
                    <image type="backdrop" url="http://hwcdn.themoviedb.org/backdrops/2ce/4bc91339017a3c57fe0072ce/transformers-poster.jpg" size="poster" id="4bc91339017a3c57fe0072ce"/>
                    <image type="backdrop" url="http://hwcdn.themoviedb.org/backdrops/2ce/4bc91339017a3c57fe0072ce/transformers-thumb.jpg" size="thumb" id="4bc91339017a3c57fe0072ce"/>
               </images>
             <last_modified_at>2010-04-26 03:26:14</last_modified_at>
       </movie>
     </movies>
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我通过使用阅读所有属性

textReader.ReadToFollowing("original_name");
string title =textReader.ReadElementContentAsString("original_name",textReader.NamespaceURI);
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但是,无论我尝试什么,我都无法读取"图像"的子节点.

c# xml xmlreader

12
推荐指数
1
解决办法
3万
查看次数

C#WinForms MouseHover和MouseLeave问题

出于某种原因,MouseHover和MouseLeave函数表现得非常奇怪.我需要做的就是,当光标在"按钮"上方时,我想让按钮可见,当光标离开按钮时,我想让它不可见.无论我尝试什么,我都无法使它发挥作用.当控件对象不可见时,似乎鼠标事件不起作用.

private void button1_MouseHover(object sender, EventArgs e)
{
   button1.Visible = true;
}

private void button1_MouseLeave(object sender, EventArgs e)
{
    button1.Visible = false;
}
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c# button visible mousehover

1
推荐指数
1
解决办法
7360
查看次数

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c# ×2

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