這段時間在vs 2003 的webform 方式下對excel 進行操作，遇到一個最為頭疼的問題就是對excel操作完畢后excel不能夠正常關閉，系統(tǒng)退出后，excel總是駐留在內(nèi)存中。但是這段代碼放到winform的程序中又沒有問題。在網(wǎng)上進行了查找也沒有找到有效可行的辦法。經(jīng)過無數(shù)次的嘗試，終于解決如下：
原來書寫如下：
private excel.application m_app;
private excel.workbook m_workbook;
this.m_app = new excel.applicationclass();
this.m_app.displayalerts = false;
this.m_workbook = this.m_app.workbooks.open(sfilepath, missing.value,
missing.value, missing.value, missing.value,
missing.value, missing.value, missing.value,
missing.value, missing.value, missing.value,
missing.value, missing.value, missing.value,
missing.value );
修改后如下：
private excel.application m_app;
private excel.workbooks m_workbooks;
private excel.workbook m_workbook;
this.m_app = new excel.applicationclass();
this.m_app.displayalerts = false;
m_workbooks = this.m_app.workbooks;
this.m_workbook = this.m_workbooks.open(sfilepath, missing.value,
missing.value, missing.value, missing.value,
missing.value, missing.value, missing.value,
missing.value, missing.value, missing.value,
missing.value, missing.value, missing.value,
missing.value );
同樣對sheet的操作如下
修改前如下：
excel._worksheet worksheet1 = null;
worksheet1 = (excel._worksheet) this.m_workbook.worksheets.get_item(ssheetname);
修改后如下：
excel.sheets sheets = null ;
excel._worksheet worksheet1 = null;
sheets = this.m_workbook.worksheets;
worksheet1 = (excel._worksheet) sheets.get_item(ssheetname);
發(fā)現(xiàn)區(qū)別了么?原來workbooks，worksheets這兩個類沒有被實例化就直接使用了，造成該類不能夠被回收。最終造成excel在內(nèi)存的駐留。
最終以如下方式釋放。
private void releaseallref(object obj)
{
try
{
if (obj != null )
{
while (marshal.releasecomobject(obj) > 1);
}
}
finally
{
obj = null;
}
}
private void release()
{
if (m_app != null )
{
m_app.quit() ;
}
releaseallref(m_workbook) ;
m_workbook = null ;
releaseallref(m_workbooks) ;
m_workbooks = null ;
releaseallref(m_app) ;
m_app = null ;
system.gc.collect() ;
}
